Below are websites, apps, and a chart to help with ear development.

Music Theory Interval Training – http://www.musictheory.net/exercises/ear-interval

Good Ear – http://www.good-ear.com/

Ear Beater – http://www.earbeater.com/online-ear-training

Musical Mind – http://www.musicalmind.org/

Apps:

Relative Pitch Interval Ear Trainer, Tenuto, InTune, TuneUp, A.P.S. Tuning Trainer