TempoPerfect Metronome - TempoPerfect is a free software metronome.
Fine Tuner - Fine Tuner is a minimalistic guitar tuner that utilizes your device's built-in microphone.
Metronomus - Powerful and beautiful online metronome
Guitaroid - Listen to Guitaroid | SoundCloud is an audio platform that lets you listen to what you love and share the sounds you create.
LINGOT - Musical instrument tuner, LINGOT is a musical instrument tuner.
AudioKit Hey Metronome - Visit the post for more.