Get yourself in the habit of reflecting on the BEST thing that happened each day. This simple app will nag you at 6PM, 7PM, 8PM, 9PM and 10PM until you enter your favorite thing from that day.
Scroll through your memories and remind yourself how awesome your life really is.
All of your memories are backed up to iCloud automatically, so they will do with you to your other devices (as long as you keep the same iTunes account).
Totally free. My gift to you. You are welcome...