Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
Symbyoz Happy Birthdays - A smarter way to keep up with your birthdays.
TickTick - TickTickis a cross-platform to-do list app & task manager helps you to get all things done and make life well organized.
SS Birthday Reminder Live - Improve personal organization and don't forget important things.
Zenkit - Zenkit is the home you always wanted for your ideas, your projects, your business.
Birthdays - A simple, straightforward app to help keep track of birthdays.