Android: the problem here is that the user may have installed multiple apps for the alarm, and who knows what he enjoys, and it is difficult to cover all possible. The tip of the iceberg on this list:
http://stackoverflow.com/questions/4115649/listing-of-manufacturers-clock-alarm-package-and-class-name-please-add
I have not seen the possibility of obtaining a list of reported alarm clocks, neither one of them.
iOS: as far as I know — no.