What are some alternatives?
When comparing Simple Habit and Sleep as Android, you can also consider the following products
Headspace - Meditation made simple. Brilliant things happen in calm minds.
SleepBot - SleepBot is a sleep tracking app available in Google Play and the Apple App Store.
Calm - Take a break and meditate.
Talalarmo - Minimalistic android alarm
AuraHealth.io - Become more mindful with 3-minute, guided meditations.
Gentle Alarm - Gentle Alarm can consider your sleepcycles to wake you up when you are in light sleep.