www.trackyourhappiness.org
I Journal
Happiness+
Mortar Men
Cyanide and Happiness Lite
Positive Thinking. The Key to Happiness
How To Be Happy
Healthy Habits (a health, happiness & wellness app)
Gratitude & Happiness (Self-help Journal, Todo, Thoughts & Mood Tracker)
Happiness Tips
Happiness Is…
Live Happy
Success and Happiness
mappiness
The Secret of Happiness
… and a lot more!