How can I change my phone's resolution?
Using adb, no root required
Use the command adb shell wm size 720x1280
Using phone, root required
Download any Terminal app, such as this one.
Type the command su to enter superuser mode, and then type wm size 720x1280 into the terminal.
Source: http://www.theandroidsoul.com/change-screen-resolution-adb-android/