Phone display is smaller compared to tablets and if you have bought an Android long back then chances are that your screen resolution is smaller. Newly launched Android phones have great resolution but your old phone resolution is not that great. Whatever may be the reason you want to experiment with your Android phone screen resolution then look at this app called LCD Resolution.
With LCD Resolution you can increase or decrease your Android phone screen resolution. This app requires rooted device for it to set resolution. Do check the compatibility of the application with your Android device. If you have connected your phone with Google account it will suggest whether the app is compatible or not.
The application requires rooted Android device and it may break some core android applications due to increase in screen resolution.
Download LCD Resolution