Mochi - Write notes and flashcards with Markdown and study them with spaced repetition.
Decks - Decks is a study application designed to keep all your stuff in one place, instead of having an app for flashcards, another for notes, and one to watch tutorials, create a deck and keep everything organized there.
Jot - The no-fuss way to take notes
Payzo - Accept credit cards with zero coding (for freelancers)
Bookmark It - Create awesome notes on YouTube videos
PayPal.Me - Request money using your own personalized URL.