We have introduce A cool app Guitar Chords for Beginners
The Secret to Chords
Know your chord formulas
works for Keyboard too
Easy Guitar Chord Book for Beginners
With this Guitar Chord Book for Beginners not only do you have beginner open position chords in all 12 keys but you also learn about chord formulas so you can find chords in other positions for guitar for yourself
Plus you can find the Major Scale in all 12 keys for both Guitar and Keyboard and chords for Keyboard too
Link to google play store: https://play.google.com/store/apps/details?id=com.wGuitarChordsforBeginners
Requirements: Android 2.1 and Up.
Available for Android.
I recommend you to download this free and awesome app.