add GridWichterle by @inmite

Author: Joker

categories/tools.md

@@ -5,6 +5,7 @@ App Name                   | Describe                  | Major Language
 [Clip-Stack](https://github.com/heruoxin/Clip-Stack) | An Android clipboard history manager app with Material Design.  | Java | [![Get it on Google Play](https://developer.android.com/images/brand/en_app_rgb_wo_45.png)](https://play.google.com/store/apps/details?id=com.catchingnow.tinyclipboardmanager)  
 [DesignOverlay](https://github.com/Manabu-GT/DesignOverlay-Android) | Android app which displays design image with grid lines to facilitate the tedious design implementation process  | Java | [![Get it on Google Play](https://developer.android.com/images/brand/en_app_rgb_wo_45.png)](https://play.google.com/store/apps/details?id=com.ms_square.android.design.overlay)  
 [Flock](https://github.com/WhisperSystems/Flock) | Private contact and calendar sync for Android. https://whispersystems.org/blog/flock  | Java | [![Get it on Google Play](https://developer.android.com/images/brand/en_app_rgb_wo_45.png)](https://play.google.com/store/apps/details?id=org.anhonesteffort.flock)  
+[GridWichterle](https://github.com/inmite/android-grid-wichterle) | This app will show grid overlay over whole system which helps you to verify your excellent app design.  | Java | [![Get it on Google Play](https://developer.android.com/images/brand/en_app_rgb_wo_45.png)](https://play.google.com/store/apps/details?id=eu.inmite.android.gridwichterle)  
 [OS Monitor](https://github.com/eolwral/OSMonitor) | Android OS Monitor  | Java | [![Get it on Google Play](https://developer.android.com/images/brand/en_app_rgb_wo_45.png)](https://play.google.com/store/apps/details?id=com.eolwral.osmonitor)  
 [Prey Anti Theft](https://github.com/prey/prey-android-client) | Android client for the Prey anti-theft software. http://preyproject.com  | Java | [![Get it on Google Play](https://developer.android.com/images/brand/en_app_rgb_wo_45.png)](https://play.google.com/store/apps/details?id=com.prey)  
 [Telecine](https://github.com/JakeWharton/Telecine) | Record full-resolution video on your Android devices. | Java | [![Get it on Google Play](https://developer.android.com/images/brand/en_app_rgb_wo_45.png)](https://play.google.com/store/apps/details?id=com.jakewharton.telecine)