ContactCATs

I made this app for learning purposes, yet someone might find it useful.
If you only use your phone to call people, and you don't call many of them, this app might be for you.

ContactCATs lets you categorise your contacts in sub-groups and quickly access them later. Create groups like

"Work", or
"School".

To me, this app is especially useful to hold a reference to people to call in specific situations, like

"Beer friends", or
"Bicycle rides".