Letter to Yourself - Send a physical letter to your future self
Chars - Unicode Symbols Keyboard for iOS
Future Me - Send an email to your future self
Falcon for iOS - Writing notes made simple
Letter to my future self - Letter to my future self is a prominent email scheduling service that gives you the opportunity to create a letter with goals and thoughts for your future self and schedule a date for sending it.
A5 - Takes notes in your browser. Elegant & simple.