Phum Keyboard is a free Android application developed by Biz Solution Co. Ltd. and sponsored by GGear Co. LTD. It is a keyboard app exclusively designed for LG Optimus Pro C660 with Khmer Unicode installed. The app does not include any fonts, so users without standard Unicode on their phone cannot use it.

Phum Keyboard provides a simple and easy-to-use interface for typing in Khmer language. The keyboard includes all the necessary characters and symbols to write in Khmer. The app has no additional features or functionalities beyond its primary function.

Overall, Phum Keyboard is a useful tool for LG Optimus Pro C660 users who need to type in Khmer language. However, it is important to note that the app is only compatible with phones that have Khmer Unicode installed and does not include any fonts.