Journaly - The customisable journal app
Letter to Yourself - Send a physical letter to your future self
Day One - A simple journal application for the Mac, iPhone, and iPad. AboutTo learn more about Day One, see these two excellent reviews . PublishPublish is not available in Day One 2.
Future Me - Send an email to your future self
Grid Diary - The simplest way to get started with keeping a diary
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.