A click that cannot drift.

The click is a single PCM buffer spanning one whole bar, handed to the audio hardware and looped there. There is no timer anywhere in the audio path, so nothing accumulates error - an hour in, the click is where it should be.

Drag vertically on the big number for a sweep, tap the tempo out and Tock averages your last few taps, or step a single BPM with ±. The tempo marking - Grave through Prestissimo - updates underneath as you go.

Tap any beat dot to cycle it accented, normal or muted. Patterns are remembered per time signature and travel with a saved song. 2/4 through 12/8 are there as presets, and Pro adds any bar length from 1 to 16 beats.

Quarters, eighths, triplets and sixteenths, cycled from one chip. The "and" of the beat sounds a step above the other subdivisions, so a bar of sixteenths has a shape rather than a rattle; triplets have no half-beat to land on and are left alone. Every tick is part of the same sample-accurate bar rather than a second click layered on top, so none of them can slip against it.

Beep, Wood, Click, Rim, Cowbell and Hi-hat, every one synthesised in code. There are no audio assets in the app, nothing to download, and nothing to load before the first beat. Three are free; Pro adds the rest.

A speaker toggle sits beside the transport: mute the click and keep the beat in your hand through haptics - rigid on the downbeat, light elsewhere. For loud rooms there is a full-screen flash on every beat, brighter on the accents.

The Apple Watch app runs on its own with the iPhone left in the case. Set the tempo with the Digital Crown, tap the beat row to accent a beat, and change the time signature, subdivision and sound without leaving the screen. Your songs and sets arrive from the iPhone, both trainers are there, and the click keeps going when the screen goes dark.

watchOS has no haptic intensity to raise, so the whole choice is which of nine named taps stands for the downbeat and which for the other beats. Each one plays as you pick it, and a silent two-bar preview lets you feel a bar before deciding - a pair can feel distinct tapped one at a time and identical inside a bar. How much of a tap a wrist notices depends on the strap and the person, so it is a setting rather than a guess.

Tempo ramp walks the tempo between two marks while you play - up to push your limit, or down, because slower is harder. Gap click drops the click for whole bars so you carry the time yourself, then brings it back.

Save a tempo with its signature, accents, click and notes under the tune's name, then load it with one tap. Duplicate a song to make the slower version of it, and search the library by name or by what you wrote in the notes. Sets arrange songs into a running order for a gig or a lesson - next and previous appear on the metronome screen itself.

"Start Tock at 120." Start and stop the click, or play a saved song by name, from Siri, from Spotlight, or in the Shortcuts app. The trainer intent is Pro, and says so out loud rather than doing nothing.

A quiet readout under the transport: the running session while you play, today's total once you stop. Nothing is kept beyond today, so there is no streak to protect and nothing to feel guilty about. Touch and hold to reset it.