Trainbell: HIIT & Tabata Timer

Trainbell is a free interval timer for HIIT, Tabata, boxing rounds, EMOM and circuit training. Set prep, work, rest and rounds, tap Start, and the workout timer keeps running with the screen off. No account, no subscription, and never an ad on the timer screen.

SET UP IN SECONDS Four numbers and a Start button: prep, work, rest, rounds. That is the whole home screen. Sets, rest between sets and a cool-down are one tap away under More options. Hold + or - to move in big steps.

BUILT TO BE READ MID-EFFORT Every phase gets its own full-screen colour, so a glance from across the gym tells you where you are. Giant steady digits, the next phase always on screen, and tap anywhere to pause instead of hunting a small button with sweaty hands.

KEEPS RUNNING WITH THE SCREEN OFF The most common complaint about interval timers is that they die in your pocket. Trainbell runs as a foreground service with lock-screen controls and times every cue from the system clock, so it cannot drift and survives the phone freezing the app. Pocket it mid-round and every beep still lands on time.

CUES THAT CUT THROUGH YOUR MUSIC Cues duck your music or podcast for a moment and hand it straight back, never pausing it. Cue volume is separate from media volume, so an audiobook at 20% and cues at 100% works. Choose beeps, a spoken phase name, vibration only, or a screen flash. A Bluetooth delay setting makes cues land on time with wireless headphones.

WHAT YOU GET FREE

Prep, work, rest, rounds, sets, rest between sets, cool-down
Full-screen phase colours, tap to pause, skip forward and back, add ten seconds
Runs with the screen off, with lock-screen controls
3-2-1 countdown and a half-way cue
Vibration-only and screen-flash modes
Separate cue volume and Bluetooth cue delay
Five saved presets, with export and import to a file
Dark theme, and a colour theme that follows your system setting
Unlimited workouts, no time limit, forever

TRAINBELL PRO, ONE PRICE, ONCE Not per month. The timer stays free forever. Pro adds unlimited saved presets, spoken voice cues, every sound pack, four extra colour themes, and removes the single banner from the setup screen.

ABOUT ADS One banner, on the setup screen, only in the free version. No ads on the timer screen, no full-screen ads, no ads on launch, no ads with sound. Not now, not later.

YOUR DATA STAYS ON YOUR PHONE No account. No sign-in. No analytics. No network calls of its own. Your presets live on the device and export to a file you control.

ONE TIMER FOR EVERY INTERVAL WORKOUT

HIIT timer and Tabata timer: 20 on, 10 off, 8 rounds is one preset away
Boxing timer and heavy-bag rounds: 3 minute rounds, 1 minute rest, bell cue
EMOM and AMRAP timer for CrossFit-style workouts
Circuit training timer and bodyweight circuits at home
Gym rest timer between sets
Sprint intervals, run-walk intervals and couch-to-5k style sessions
Stretching, mobility and yoga flows
Anything that is "do this for a while, then that for a while, several times"

Trainbell is a timer, not medical advice. Consult a professional before starting a new exercise programme.

Questions or feedback? Reach out any time from Help and Contact in Settings.