I've released Calcutron and Calcutron Lite version 1.1.0 onto the Android Market today. The big change is that in the full version I've added Random mode. In Random mode each equation you make will use a different function randomly, you will have to check the entry button to see what you are using. It mixes up the gameplay a bit and so far seems fun to me.
Since I've added a new mode to the full version I decided to open up Subtraction on the Lite version, giving you access to Addition and Subtraction for Timed and Clear gameplay.
The full version of Calcutron is available on the Android Market for $1.00 and the Lite version is available for free.