What are some alternatives?
When comparing Calm and Free Alarm Clock, you can also consider the following products
Headspace - Meditation made simple. Brilliant things happen in calm minds.
Gnome Clocks - Clock application designed for GNOME 3
Simple Habit - Our mission is to empower humans to stress less, achieve more, and live better. Meditate today!
Talalarmo - Minimalistic android alarm
Smiling Mind - Promotes mindfulness and meditation for young people
KTimer - KTimer is a little tool to execute programs after some time.