NOME is a pro metronome for iPhone and Android.
Big numbers. Big buttons. Built for working musicians.
space to start/stop, ↑↓ to nudge · The app does the rest.
The tempo fills the screen. One glance from across the room. If you can see the stand, you can see the tempo.

Beats per bar from 1 to 9, with a downbeat that cuts through. Save every piece — tempo and meter together — and recall it mid-rehearsal.

Through the mute switch, behind the lock screen, all rehearsal long.