Today only, Nov 20, 2013, AffinityBlue has their Tunable: Tuner, Metronome, and Recorder in the Amazon AppApp Store for FREE (regularly $1.95) for a limited time.

Tunable is a chromatic tuner, tone/chord generator, metronome, and recorder that helps you learn to play steadily, in tune, and on beat. Featuring a unique “tuning history” display for visualizing pitch over time, Tunable is the perfect toolkit for beginning to professional musicians.