A free app for Android, by JMBraga.

Cable Remote Control is a handy app for controlling your cable or satellite set-top box with remote control. It’s a universal remote control for all cable and satellite set-top boxes. With a few simple steps, you can control your TV, DVD, Home Theater, or any other set-top box with remote control via the internet. You don’t need to worry about installing any additional hardware or drivers. The app will work with most of the latest set-top boxes and TV remotes.

The app has a built-in keyboard that you can use to type in commands. It supports many popular commands like power on, off, mute, volume up, volume down, channel up, channel down, etc.