DisplayTester makes it possible to test almost every aspect of your device's LCD/OLED screen. Using Google Cast it is possible to test the display quality of your TV. It is designed to allow full screen testing also on devices with soft keys (hiding the soft keys in ICS and later, immersive mode in KitKat and later).------= Free features =-
◆ Dead pixel test: detect "dead pixels" by displaying a series of solid background color pages
◆ Color tests: contrast, gradient (banding) and saturation tests
◆ Gamma calibration tests (grey/red/green/blue)
◆ Viewing angle tests (This is useless for OLED displays)
◆ Multi-touch test
◆ Display performance tests
◆ Repair burn in - scrolling black & white bars
◆ Display measures info: screen size, GPU type, dpi, density-independent pixel size, OpenGL 1.x info, pixel format
◆ Real world pictures for reference and comparison
◆ 4-color gradient test with orientation change correction (Android 2.2 and higher)-= Pro features =-
◆ No splash screen
◆ Full Google Cast support
◆ Repair burn in - noise (white, b&w, red, green, blue) => Only Android 2.2 and higher!
◆ Pixel format & dithering tests
◆ Built-in font styles test
◆ Manually DPI measurement
◆ Color charts
◆ Touch screen dead spot tester
◆ System Fonts tester
◆ DIP / PX calculator-= Soft key hiding in ICS/Honeycomb/JellyBean =-
Use the preferences menu option for this or simply long touch the display during a test is running.-= Gestures =-
◆ Slide left-right: change test image
◆ Slide up-down: change brightness
◆ Long touch: switch between full screen and normal screen (Android 3.0 and higher)
◆ Double tap: hide or show the test specific settings dialogue (if available)When the soft keys are hidden it is not easy to advance to the next screen: First tap to make the buttons appear, then a quick swipe for the next screen before the buttons are hidden again.-----
Please consider purchasing the Pro version to support further development.If you are having a problem or you have a suggestion about a missing feature, the ONLY way it will get done is if you email me! :)

// Option A //

To download Display Tester mod from HappyMod.com.
You need enable the option "Unknown Sources".
1. Click on the above link to download Display Tester mod APK.
2. Save the file in your device Downloads folder.
3. Now tap on Install and wait for the installation to finish.
4. Once it is done, open the game and start playing it right away.

// Option B //

To download Display Tester from HappyMod APP, you can follow this:
1. Open your browser and download the HappyMod APK file from HappyMod.com - the only official website of HappyMod.
2. Open Android Settings and go into Privacy or Security.
3. Tap the option to Allow Unknown Sources and enable it.
4. Go to your Android downloads and tap the APK file.
5. Follow the directions on the screen to install it.
6. Search Display Tester in HappyMod App.