Well, to write the code you'd need some knowledge of programming. But some top of my head random example would be, if I miss a call from the tax agency, add an item to my todo list to call the tax agency back. Or if a number that I don't have in my contacts, and it starts with my area code, ring with a specific ring tone, so I know I should probably answer. Or for example you could have logic when a text with certain content from a certain person is received.