Visibility of System Status

• Provide informative feedback for all actions.
• Clear language.
• No tech-speak (proportional to the problem).
• No ambiguity.
• Keep the user informed about what is going on.
• Indicate progress in task performance.

Match Between System and The Real World

• Mirror the language and concepts user would find in the real world based on who their target users are.
• Contain familiar terms and natural language.
• Mataphor from the real world.
• Use user’s background knowledge.
• Apply rules learned by users in the real world.
• Meet expectations.
• Follow real-world conventions.

User Control and Freedom

• Undo and redo should be supported
• Backspace to return is a pattern
• Forgiveness: make actions reversible.
• Ability to cancel or re-order tasks.
• Allow the user to initiate and control tasks.

Consistency and Standards

• Same things look the same.
• Reduce the number of representations.
• Conform to plataform interface conventions or popular conventions.
• Reduce learning.
• Reduce investigations of the digital space
• Eliminate confusions.
• Users apply rules learned in others products.
• Meeting expectations.
• Show similar info at the same place on each screen.
• Icon that represents one category or concept should not represent a different concept too.
• Apply UI element as they are originally.

Error Prevention

• Potential erros are kept to a minimum
• Prevent erros from occuring in the first place
• Understand the user’s language
• Indentity cues between actions and user’s goal.
• Diferenciate primary to secondary actions (e.g. by size)
• Lock buttons that should not be used.
• Give suggestions to the users (e.g. autocomplete inputs)

Recognition Rather than Recall

• Minimize the cognitive load
• We are only caple of maintaining around five items in our short-term memory at one time.
• Recognition involves perceiving cues that help us reach into out vast memory.
• reduce the use of the short-term memory.
• See-and-point instead of remember-and-type.
• Make the repertair of available actions salient
• Provide a loist of coices and piciking from lists.
• Visible objects, visible results.

Flexibility and Efficiency of Use

• Less interaction that allow faster navigation.
• Provide a great way to work for novices and shortcuts for advanced users.
• Satisfy users at all levels of expertise.
• Use shortcuts: Accelerator to speed up dialogue.
• UI should be customizable by the users to suit their needs.
• Physical interactions with system feels natural.

Aesthetic and Minimalist Design

• The display must be reduced to only the necessary components for the current task.
• Clearly visible.
• Users can drilldown into more specific contents from a small number of options.
• Keep screen clutter to a minimum.
• Only give your user what they really need at that point.
• More needed than ever
• Try not to add more fuel to the fire than absolute necessary.
• Try not to drown the users in information.
• Information overload or infobesity ir infoxication

Help User Recognize, Diagnose and Recover from Errors

• Complementation to the user needs of be informed of system status.
• Assume the users are unable to understand technical terminology.

Help and Documentation

• Depending on the type of solution, documentation may be necessary.
• Use bullet points
• Step-by-step instructions
• Organize in categories
• In small pockets, to limit the amount of info presented in one go.

Reference

Interaction Design Foundation

Nielsen and Molish’s 10 UI Guidelines in Bullet Points was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

Positive transfer happens when you start to do a task similar to a task that what you have already done. You are familiarized with that kind of task and can use an acquired ability or experience during perfoming of a task in performing another similar task. Negative transfer is the opposit, happens when you can’t transfer an experience of performing a task to another similar task because the process is different.

Consistency is the root of this case. Keep the consistency and follow the patterns in the user inteface allow positive transfer and an inconsistent user interface design can be a source of negative transfer.

When users have developed ingrained skills, or well-rehearsed methods of control, they can impede performance on proceeding tasks in which similar skills or manoeuvres are necessary — Interaction Design Foundation

Inconsistency induces more errors, slows down task performance (efficiency), forces the user to resort to a more conscious and effortful mode of operation because the user must to identify “how does it work?”. In other way, consistency allow the user to carry out tasks quickly or even automatically (“without think”), reducing the error possibilities or bad user experiences.

Consistency should be avoided when unconscious, repeat selections need to be prevented. It’s common in dialogs where we ask the user if he is sure of an action. “Are you sure that you want to delete this item?”. Normally, the Ok button is showed left of the Cancel button, it’s a pattern, but if you want to prevent the user click on Ok automatically,without really think in what he is doing, you can break the consistency and change the buttons aside.

Reference

Interaction Design Foundation

Positive and Negative Transfer was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

Each process has its own limitations, and the designers must to take care of it, relieving the user of tasks that over-burden them, simplifying tasks and providing a better user experience.

Each cognition process are related to strengths and weaknesses of a user as we can see bellow:

The design challenge: As a designer you should allocate tasks to the user and computer according to which does them best. Relieve users of the tasks they find difficult or even impossible and allocate them to the computer.

Tasks that involve creativity, subjectivity or learning must be allocated to the user. The human mind might be an amazing thing, capable of storing an unlimited amount of information, but it has clear limitations, such as a rapidly decaying working memory, inconsistent access to long-term memory and slow processing. — Interaction Design Foudation

An user probably will prefer an alternative product instead of yours if it provides a better cognitive support. So, understand each one and take care of limitations is important for your product acceptance.

Attention

Attention is the mental process of select or ignore sensory information from our environment.

Unless we have undertaken significant amounts of practice performing two tasks simultaneously, it is very rare that we can achieve equal levels of performance in both tasks compared to when they are carried out individually. This is especially so when performing two tasks using the same sense (i.e. two visual tasks, two auditory tasks and so on). — Interaction Design Foundation

So, avoid to force your user to do two tasks at the same time, especially tasks that use the same sense.

Bottom-up x top-down perceptual processing

A top-down process is like trying trying to find Waldo in “Where’s Waldo?”. You start with an internal “high-level” goal, which determines where you look next. You are looking “for” something, so higher-level brain areas “prime” the low level visual areas to detect that pattern. — Paul King on Quora

Top-down processing is thought to be controlled by the central executive (a memory system in which prior experience and knowledge influences our interpretation of and interactions with the environment) in working memory, which is a concept established by Alan Baddeley and Graham Hitch in 1968 that built on the previous notion of short-term memory as a simple store for retaining information for a very limited period of time. — Interaction Design Foundation

A bottom-up process occurs when something unexpected is moving in the corner of your eye and catches your attention. This causes you to look over and react. The signal causing this chain of events originated in the environment. — Paul King on Quora

Bottom-up processing involves the automatic allocation of attention when one of our senses is stimulated by the properties of an object in our environment. — Interaction Design Foundation

Designer must to take care of bottom-up perceptual processing because it can allocate the user attention in a important moment (during an important task) for something not so important and, as the user can’t achieve equal levels of performance in two tasks simultaneously, he will lose efficiency.

Memory

Memory is the mental process responsible for the encoding, storage and retrieval of information received.

Once information is received by one or more of our sensory organs it is retained in one of the modality-specific sensory stores (i.e. visual sense store for visual information, auditory sense store for auditory information and so on).

Short-term Memory

Human attention is limited and we are only capable of maintaining around five items in our short-term memory at one time. — Interaction Design Foundation

Don’t force the short-term memory of the users. Always help them to remember/recognize things through cues that help them reach into the vast memory. Avoid the overload of this kind of memory.

If attention is allocated to a particular element of the sensory steam then it is maintained for a maximum of 18 seconds (Brown and Peterson, 1958) in short-term memory. Short-term memory has a limited capacity generally found to range between 5 and 9 distinct items (Miller’s magical number 7 + or — 2) — Interaction Design Foundation

With practice we are able to retain larger numbers of items in short-term memory, through a process of chunking; which involves the mental grouping of items into meaningful clusters. — Interaction Design Foundation

Designers must to take care with the number of items that the systems is forcing the user to memorize. It’s possible throught the use of standards on the template, icons and navigation and avoiding the infobesity. Even if the number of items is smaller than 9, the system must to provide cues to facilitate the user to remember.

Language

Language is the mental process that involves learning, understanding and producing meanings. The responsibility of the designer is to use the most appropriate (familiar) language for their intended users and that fits for each given domain ((therminology).

The designer communicates with the user indirectly, without the opportunity to hear or see the specific queries, problems or needs they have. Therefore, the designer requires knowledge of who their users will be, what they might want and need in the design and any potential problems that might occur beforehand, so they can anticipate what must be included in the device or system design. — Interaction Design Foundation

Reasoning

Reasoning may be defined as the set of mental processes used to derive inferences or conclusions from premises. Reasoning is not logic. Logic is more like a component of reasoning, because it refers to the application of rules, norms and heuristics (rules-of-thumb) during reasoning. Reasoning can include steps that do not conform to logic, such as choosing incorrect actions on purpose to test something.

A reasoning can be deductive or inductive:

In a deductive system we are able to reason with a high degree of certainty, on the basis of the premises of an argument, until we reach conclusion. In contrast to deductive inferences, inductive reasoning does not guarantee that the correct conclusion will be made; as such inferences are based on prior experiences and propositions rather than concrete rules, facts or algorithms. — Interaction Desgin Foundation

Problem-Solving

The mental processes involved in the development of ideas, strategies and behaviours that help us achieve our aims and objectives. There are many lists of characteristics that define a problem-solving, and between all of them we can quote three characteristics:

1. Goal directedness — Behaviour is generated on the basis of a current goal.
2. Sub-goal decomposition — Not always a goal can be reach directly. Some goals are complex and involves a deconstruction of the overall goal into the necessary component behaviours, in other words, a desconstruction of the goal in sub-goals and to reach the goal we must to reach sub-goals.
3. Operator selection — Each sub-goal is composed by various actions and select these actions and the sequence to reach a sub-goal is an characteristics of a problem-solving. each sub-goal involves the selection of an appropriate action that fits into the overall sequence.

With practice we no longer have to deconstruct the goal into its sub-goals and actions, instead we can unconsciously select the appropriate actions required to complete the overall goal. Practice reinforces the appropriateness of these actions and the sequence we must perform them in. — Interaction Design Foundation

Practice is important to the development of automatic problem-solving behaviour, designers must attempt to limit the amount of practice required before users reach this point of automaticity. One way of simplifying the problem-solving process is to make sure the tools required are as visible as possible.

Decision making

The problem-solving involves the generation of possible problem-solving behaviours, decision making involves the selection of the best available option from the problem-solving process.

It was originally assumed that decision making is a rational process, which is based on the selection of the best option according to objective thinking. However, this has since been replaced by the notion of subjective decision-making, which is based on emotional, dispositional, social and situational factors. — Interaction Design Foundation

Commonly, the selection of a solution that happens in a decision making involves a comparison of risks and the option with less risks is chosen. The users have fear of compromise anything on the system, so, it is important to minimise the costs associated with users’ actions, so they cannot cause damage and they feel able to move freely through the system or interact with a device confident.

Conclusion

Six mental processes

• Attention is the mental process of select or ignore sensory information from our environment.
• Memory is the mental process responsible for the encoding, storage and retrieval of information received.
• Language is the mental process that involves learning, understanding and producing meanings.
• Reasoning may be defined as the set of mental processes used to derive inferences or conclusions from premises.
• Problem-solving is the mental processes involved in the development of ideas.
• Decision making involves the selection of the best available option from the problem-solving process.

Important to know

• An user probably will prefer an alternative product instead of yours if it provides a better cognitive support.
• The designer requires knowledge of who their users will be, what they might want and need in the design and any potential problems that might occur.
• The designer must to avoid to force your user to do two tasks at the same time, especially tasks that use the same sense
• Designers must to take care with the number of items that the systems is forcing the user to memorize.
• Always help the user to remember/recognize.
• The designer communicates with the user indirectly, without the opportunity to hear or see the specific queries, problems or needs they have.
• Designers must attempt to limit the amount of practice required before users reach this point of automaticity.
• It is important to minimise the costs associated with users’ actions to they feel able to interact without fear.

Reference

• Interaction Design Foundation
• Paul King on Quora — https://www.quora.com/What-is-the-difference-between-bottom-up-and-top-down-perceptual-processing/answer/Paul-King-2?srid=48sI

Human Cognition was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

Interaction Design is focused on the user and its needs, trying to provide the best user experience during interactions.

Interaction designers are to the field of design as architects are to the building industry. They are both concerned with ensuring people can move freely, safely and securely, that the features necessary for everyday living are accessible, and that all of the individual components provide a cohesive experience.- Interaction Design Foundation

If interaction design focus on user needs, user feeling and user smooth moviments between features, a big problem is design blindly, without know who we are designing for. It’s not always completly possible and, consequently, we can get another big problem that is design basing in our own thinking, rather than what they actually want or need.

The Process of Interaction Design

The process has four stages and it can be repeated in a iterative process until all problems are eradicated and the user needs are satisfied and a good user experience are provided.

1. Establishing Requirements — It’s important to answer question about the project in order to establish requirements. Some good questions to be done are:

• What does the user need from the design?
• How easy is it to use the system or product?
• Does it fit the context?
• Does it provide the user with sufficient means of completing their device or system-based aims and objectives?
• Does it have superficial appeal?

1. Designing Alternatives — All the process try to reach the best design to the user. So, if any problem is identified, an alternative design must to be done.
2. Prototyping — In every phase of this iterative process, is important to prototype and trial your design. It’s importante to trial your design to ensure a good user experience and prototypes allow to test interactions with real users in a real context.
3. Evaluating — It’s the sum of all the prior stages. The users opinions are considered and the use of prototype is observed and documented.

Resource

Interaction Design Foundation

A little about Interaction Design… was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

Julian B. Rotter (1966), a world-renowned psychologist, has realised some studies about personality focusing on sense of control over events. He referred of this dimension of personality as ‘locus of control’ and has defined two kind of people, people with ‘external locus of control’, who believe that events are down to fate and believe that external influences are responsable for the results, and people with ‘internal locus of control’, who believe that they are in control of events and believe they are responsable for the results.

The studies of Spector (1982) shows that the performance of a person depends of his ‘locus of control’. Workers with ‘internal locus of control’ are more successful than their ‘external’ counterparts. But, don’t think that it’s a cause and effect correlation, because people may come to develop an ‘internal locus of control’ following success and not just success be a direct result of a person with ‘internal locus of control’.

Agree with Spector (1982) is easy because ‘internal locus of control’ workes believe that the results of their works a their own responsability, so we can expect more efforts from them than from ‘external locus of control’ workers. Lied and Pritchard (1976) sad exactly that in two main expectancies of people with ‘internal locus control’:

1. they expect effort will result in better performance
2. they expect good performance will ultimately lead to rewards.

Why I’m telling it? Because you should design your applications thinking on support this expectancies of people with ‘internal locus control’. Give freedom and control of all for your users, because this kind of person believe it is in control of all events and it likes freedom and control. Give to the user the ability of do, redo and undo things. Allow the users to terminate this action or cancel it to do another thing, in other words, allow them to control everything. How much more effort an user do in your application, better performance they must to feel and more reward they must to receive.

Resource

Interaction Desgin Foundation — UI Design Patterns for Successful Software (https://www.interaction-design.org/courses/ui-design-patterns-for-successful-software)

Thinking on Internal Locus of Control was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

Strive for consistency -The users should feel familiar and comfortable with the digital landscape to achieve their goals more easily and we can reach this feeling keep standards and consistency in the layouts, icons and etc.

Enable frequent users to use shortcuts. The efficiency of the system can be improved through shortcuts. The users can achieve their goals more quickly.

Offer informative feedback. The system must to provide to the user feedback informations like “where you are” and “what is going on” at all times and these informations should be human-readable.

Poorly designed error messages often show an error-code that does not mean anything to the user. As a good designer you should always seek to give human-readable and meaningful feedback. — Interactin Design Foundation

Design dialogue to yield closure. Always feedback all users actions, telling them if it was successful or something wrong has happened.

Offer simple error handling. Systems should be designed to be fool-proof, but when a error happens, it should provide a simple message with intuitive step-by-step instructions to solve the problem. Don’t cause pain in the users! They don’t like be wrong or feel shame or feel as a fool!

Permit easy reversal of actions. Always permit to the users reset their actions with an obvious way.

Support internal locus of control. The users must to feel in control of everything to be comfortable. They can initiate an action, terminate this action or cancel it to do another thing.

Reduce short-term memory load. Don’t force the short-term memory of the users. Always help them to remember/recognize things through cues that help them reach into the vast memory. Avoid the overload of this kind of memory.

Human attention is limited and we are only capable of maintaining around five items in our short-term memory at one time. — Interaction Design Foundation

References

Interaction Desgin Foundation — UI Design Patterns for Successful Software (https://www.interaction-design.org/courses/ui-design-patterns-for-successful-software)

Shneiderman’s Eight Golden Rules in my words was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

There are many occasions where the user needs to see a list of options, categories, commands or other related items but when they make a selection they still need the list in view.Two-panel selectors are commonplace in web and application design as they enable users to view the contents of individual files, emails and other content-carrying items in one panel and quickly switch between them in another.

Benefits

The users don’t need to skip between different sections of the applications in order to gain access to the list of options or individual contents. So, this pattern minimizes the number of necessary intermediate steps and interactions.

A movement from a section, windows or page to another usually demands the users reorient themselves every time they reach a new position, what is a cognitive effort. Using this pattern the spatial location is preserved and the user don’t need to reorient itself in the screen.

Spatial memory is limited, it is estimated that we are capable of maintaining only nine distinct items in an active state; designs that involve movement from one region of the user interface to another interrupt the experience of scanning options and checking their contents, which forces the user to maintain information in short-term memory. — Interaction Design Foundation

Using this pattern, the users don’t need to maintain infromation in short-term memory because everything that they need to reach is in the same section, windows or page. They don’t need to remember where things are because it was never removed from view.

How to Implement

• Users tend to look from left to right and top to bottom (as per the viewing direction followed during reading), therefore, the list — being the user’s first port of call — should be placed either above or to the left of the panel in which the selected item contents are displayed.
• To make the interactive and viewing experience as cohesive as possible, the contents of an item should appear immediately in the second panel, following interaction with the corresponding item in the first panel list. Even brief delays can negatively affect user experience, so every effort should be made to ensure the contents appear as quickly as possible.
• List options are generally arranged vertically and there are often times when the number of options exceeds the available space of the panel so scrolling must be enabled.
• The selected option in the first panel must also be distinguished from the rest to provide the user with a means of instantly determining which item contents they are currently viewing.

References

Book — Designing Interfaces (http://designinginterfaces.com/patterns/two-panel-selector/)

Interaction Desgin Foundation — UI Design Patterns for Successful Software (https://www.interaction-design.org/courses/ui-design-patterns-for-successful-software)

Two-Panel Selector was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

Interaction design dilemma

Users want power, features, and enough options to handle all of their special needs — Vs. — Users want simplicity; they don’t have time learn a profusion of features in enough depth to select the few that are optimal for their needs.

A user might only want to change the icon name for their computer speakers, whilst another user might want to carry out more detailed changes, such as altering the speaker enhancements to suit their listening environment. How do you provide both users with sufficient means to complete these tasks without flooding the user interface with all the information related to these different tasks?- IDF

Progressive Disclosure as a Solution

You should must to provide all features but you should to display immediately only what is important, giving to the user an way to move to the not so important features without to have to re-orient itself in the UI.

1. Initially, show users only a few of the most important options.
2. Offer a larger set of specialized options upon request. Disclose these secondary features only if a user asks for them, meaning that most users can proceed with their tasks without worrying about this added complexity.

You should ensures the user only has to attend to a confined region of the user interface and, at this region, you should devide the features into distinct, yet instantly accessible, areas, showing one area at time.

Progressive disclosure defers advanced or rarely used features to a secondary screen, making applications easier to learn and less error-prone. — Jakob Nielsen

Each area represents a level of the features and the first area or level with the contain most important features and must to be immediately displayed.

Levels

Frequency-of-use statistics can help you prioritize the features and chose the most important to display in the first level area. But you have to discern whether a page gets many hits because users want it or because they simply enter the page by mistake.

The first display can’t contain:

• too many options or you’ll fail to sufficiently focus users’ attention on truly important issues
• confusing features or you’ll slow down user performance

Don’t forget it must be obvious how users progress from the primary to the secondary disclosure levels. Make the mechanics of this operation simple and label the button or link in a way that sets clear expectations for what users will find when they progress to the next level

Benefits

• Gives the user a sense of control over events in the user interface
• Users see what they want
• Users will see only the information related to the task that they are performing
• Save the user from assessing the user interface in an attempt to tease out relevant information from the array.
• The ability to convey exactly what is important to the user
• For novice users, this helps prioritize their attention so that they only spend time on features that are most likely to be useful to them.
• For advanced users, the smaller initial display also saves them time because they avoid having to scan past a large list of features they rarely use.
• Promotes a better understanding of the system

Step-by-step Progressive Disclosure x All-Category-Options-at-Once Designs

Step-by-step progressive disclosure designs, such as those used when filling out online order forms, begin by showing the user a small set of options. Depending on this initial selection the user is shown further options specific to that first choice; constraining the user to only those options relevant to the current task and in accordance with previous choices. In contrast, all-category-options-at-once designs, such as the speaker settings panel, allow the user to move between different sub-sections as and when they please.

When to Use or Not?

Progressive disclosure must only be used where all of the necessary information for a particular task can be displayed in full view in one section of the user interface and there is no benefit to displaying information from different sections together

One potential pitfall is using progressive disclosure when the user is meant to compare different sets of information. If data sets are placed in different sections of a panel, window or web page, skipping between these locations interrupts the comparative process and forces the user to rely on what they can recall from the previous, now out of view, section. Short-term memory is very limited, with an approximate capacity of 7 distinct items and an estimated duration of 18 seconds.

Resume

• User only has to attend to a confined region
• Devide the features into distinct, yet instantly accessible, areas
• Provide all features but display immediately only what is important
• The immediately displayed area is the first level with the most important and most frequently used features
• The secondary levels contains more advanced features and consequently less frequently used features
• Give to the user an way to move to the not so important features without to have to re-orient itself in the UI.
• Make applications easier to learn and less error-prone.

References

Nielsen Norman Group — Progressive Disclosure (https://www.nngroup.com/articles/progressive-disclosure/)

Interaction Desgin Foundation — UI Design Patterns for Successful Software (https://www.interaction-design.org/courses/ui-design-patterns-for-successful-software)

Progressive Disclosure was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

Linux Process

In a Linux, each user has its own process and a unique ID. Every user has access to private resources proctected by permission and any user (except the super user) can access another user’s private resource. In Android, the same thing happens, but instead of users we have applications.

By default, applications and process have a one-to-one relationship, but if required, it is possible for an application to run in several process, or for serveral applications to run in the same process.

Starting a process is slow and the comunication between process is slow too. A process allocates memory for its own substantial resources. So, an application that uses more than one process to work need to lead in consideration the loss of performance that will happen.

Zygote

The Android try to shorten the statup time of the applications, because start the runtime and the Linux process is not light. It does it throught the Zygote, that is a process that has the entire set of core libraries preloaded. Every new process created is a fork from Zygote withou copying the core libraries, because the Zygote share it with all process.

____

Application Lifecycle

When any application’s component is initiated for execution, the application is started. So, any component can be the entry-point for the application starting.

1. A component is called
2. Start Linux process
3. Create a runtime
4. Create Application instance
5. Create the component

Application instance is the first component to be instantiated in a process and the last to be destroyed.

The runtime avoids to destroy all resources of an application when it’s killed because a user may request the same application at any later time. The runtime only destroys the resources when a number of live applications leads to an actual shortage of resources across the system and the system needs to kill the entire process. So, the application is started when one of its components is called, but it’s not completly terminated even when all of its components have been destroyed.

The runtime is responsible for make the lifecycle of the application happens completly, but the Linux process can be killed before the runtime had a chance to call every lifecycle method of the components. It can happen when the system needs located resources. For example, the method onTerminate() of the Application instance cannot be called by the runtime during the application killing because the Linux process was killed by the system before.

Efficient Android Threading Book — My Compilation of Chapter 1 was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.

I’ve verified if I was submiting the debug version of my apk and I’ve confirmed that I was submiting the release version generate in Build > Generate Signed APK. I’ve tried to use the zipAlignEnabled true in the release buildType on gradle script but it has not worked.

So, why is it happening?

Simple, Its a problem in gradle plugin version 2.2.0-alpha3… This version doesn’t work well with the zipAlign. I’ve made some testes to check if this post that I’ve found is valid and it is.

With gradle 2.1.2 ZipAlign works fine;
With gradle 2.2.0-alpha2 ZipAlign works fine;
With gradle 2.2.0-alpha3 the APK is not zipaligned.
With gradle 2.2.0-alpha4 ZipAlign works fine, but it's still incompatible with AS2.2

Today was release the alpha4 version and the problem with the ZipAlign has desapeared, but when I debug my app I receive a warn about another problem : It’s still not compatible with Android Studio 2.2 preview 3.

That’s another good post about this problem.

Android Gradle Plugin 2.2.0-alpha3 is missing zipalign was originally published in Younger Auad on Medium, where people are continuing the conversation by highlighting and responding to this story.