For almost 2 years I’ve used Cleartune and Tempo as my choice of iPhone apps for tuning and metronome. Planet waves just released 2 apps that blow them out of the water. Both apps have very useful features and do their jobs extremely well. I definitely will be retiring my old tuner and metronome. My favorite feature is being able to put a kick on 1 and 3 and snare on 2 and 4 in ProTempo.
Check them out.
