I was changing strings on my git-fiddle last night, went to reach for the digital guitar tuner and ....battery was deader than a door nail! Being it was the only 9 volt battery within a 500 mile radius, I REMEMBERED that there was an APP in the market called gStrings! It's a full blown guitar tuner and it saved my night last night! It even seemed to work better than my guitar tuner did! Happy story, The End!