Sleep Cycle - Bio-alarm clock that wakes you up at optimal times based on your sleep patterns.
SleepBot - SleepBot is a sleep tracking app available in Google Play and the Apple App Store.
Talalarmo - Minimalistic android alarm
Pillow for iOS - An iOS companion that helps you sleep better 💤
AlarmDroid - AlarmDroid is an alarm application that is only available on Android devices and possesses many interesting features.
Sleep Time - Alarm Clock - Sleep Time provides insight into your sleep patterns. By tracking your level of movement throughout the night, Sleep Time generates customized sleep data in easy-to-read charts.