Over time it has won my heart and this is now my goto tuner. If you use any instrument including voice it is also a perfect tool for practicing keeping in pitch as waveform is graphically represented in a longer time than any other tuner. Plus it can keep track of your progress.
Tried it a little bit to train my vocals and even though I do not do it regularly it would be essential if I ever got serious about my singing.
Includes other useful functions to and even though there is a lot of free tuners this is worth paying for even if it was just the tuner and the way it works...