I found a great free chromatic tuner in the Android Market called gstrings. It’s accurate, has a really smooth moving needle, and a digital readout of your exact hertz. There are million other useful looking settings. This app has tons of potential beyond just telling you what you’re playing. I’m looking forward to playing with it more and seeing what all it can do. I tested it side by side against my Korg and it consistently gave me the same read-outs through a full scale, with much smoother needle motion than the Korg. It’s very responsive to changing notes on auto mode. Just to see what it would do, I pulled it out before a concert today, to see if it could hear me while other musicians were also warming up. No dice there, but I’m sure if I played around with the mic sensitivity settings, I could have gotten better results. It works great in a quiet room.
As I was drafting this, during intermission at an afternoon concert, I noticed some of the guys singing into iPhones. Turns out they were playing with iPhone tuners, so I got some recommendations for things to try on the iPhone platform as well.