Justune Guitar Tuner - Justune - a guitar tuner
Pitch Grid Test - Measure your pitch-distance precision recognition. The resulting relative pitch indicator shows your sense for relative pitch.
oTuner - oTuner is a Free, Open Source Chromatic Tuner for Windows and Windows Mobile (or Pocket PC).
TuneCrack - TuneCrack stands for: Crack the tuning problem. The importance of tuning is often underestimated.
PitchPerfect - PitchPerfect is a free guitar tuner that is developed by NCH Software. It combines automatic note detection with a user-friendly interface to provide accurate tuning for a variety of six-string instruments.
Guitar Tuna - GuitarTuna is the easiest, fastest and most accurate guitar tuner app out there!