What apps? MorphOS specific with MUI & etc? None i know. But, there are plenty of other apps out there in Pascal, if you want to study the language. The main examples being the compiler itself (yes, FPC is written in FPC, sources here) and Lazarus, which is a Delphi-alike RAD environment based on and written in FPC, and also open source. MorphOS-specific sources of FPC runtime libs are here and also contain a good batch of information.

Or you think about something else?