Journal - Organize all your ideas
Future Me - Send an email to your future self
Journalistic - A simple, yet powerful micro journaling app
Dabble Me - Your own private place to write. A journal/diary to help you remember what's happened in your life.
Journaly - The customisable journal app
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.