Sleep Cycle

Sleep Cycle calculates four bedtimes that land you at the right wake time, based on 90-minute sleep cycles. Enter the time you need to wake up, and the app works backwards to find when you should fall asleep. The four options let you pick the bedtime that fits your schedule.

Users who wake up wrecked find that hitting the right sleep cycle makes a noticeable difference.

Key features:

• Four calculated bedtimes for any wake time

• 90-minute sleep cycle calculations

Free:

• Wake time calculator