Vibration on calling is a simple and free Android app developed by mkh that allows your device to vibrate continuously when you receive an incoming call. It is a useful tool for those who have experienced issues with their device not vibrating when the screen is closed. This app is specifically designed to work with PLANET COMPUTERS' Cosmo Communicator, which only vibrates once when there is an incoming call with the screen closed.

The app is easy to install and use. Once installed, it runs in the background and automatically vibrates your device when you receive a call. The app does not require any additional setup or configuration, making it a hassle-free solution to your vibration issues.