Reaction & interval trainer

Master your speed, reflexes & endurance

An interval timer that calls real commands while you train — for boxing, kickboxing, MMA and fitness. Build your own rounds, combos and voice cues.

Start free. Upgrade to Pro or Coach when you need more trainings, custom commands, and advanced callouts.

Live session — big commands while the round clock runs.

Live session — big commands while the round clock runs.

How it works

  1. 1

    Build a training

    Set prep, rounds, rest and warning times. Add the signals you want called — punches, colors, directions or your own labels.

  2. 2

    Tune the callouts

    Pick fixed or random intervals, block consecutive repeats, stack combos, and choose TTS or your recorded voice.

  3. 3

    Train full-screen

    Start the session: big commands, beeps, optional flash/flashlight, pause and skip — screen stays awake until you finish.

Inside the app

Real screens from the phone — session, home and the workout builder.

Live session — big commands while the round clock runs.
Live session — big commands while the round clock runs.
Home — streak, weekly stats and your trainings ready to start.
Home — streak, weekly stats and your trainings ready to start.
Builder — rounds, rest, signals and randomizer rules in one place.
Builder — rounds, rest, signals and randomizer rules in one place.

What is inside

Voice callouts, rounds, randomizer, sharing and offline training — ready to use.

Custom voice commands

Numbers, colors, directions, punch labels and mic-recorded samples — with TTS speed control.

Advanced interval rounds

Prep, round, end-warning and rest — tuned for boxing, MMA or any fitness interval work.

Smart randomizer

Fixed or random callout gaps, no consecutive repeats, unique-in-combo rules and shuffle coverage.

Combos & sequences

Single signals, multi-hit groups, cross-category mixes with exclusions, or ordered scenarios.

Live session coach

Full-screen workout UI with pause, skip, mute, large command display, beeps and wake-lock.

Flash & flashlight cues

On-screen flash modes and optional device flashlight synced to every command.

Themes for every setting

Per-workout looks: dark, light, high-contrast outdoor and neon — pick what stays readable in the gym, sun or low light.

Activity & streaks

Streak, workouts, time and commands over 7–30 days — plus schedule filters for what is due.

Share & import

Send a training or category via link and QR; import on another device by camera or image.

PWA, offline & APK

Train without internet as an installable PWA, or grab the Capacitor Android APK with OTA updates.

Multilingual voices

UI in several languages; training voice can target sport locales such as Muay Thai or BJJ.

Use it on your phone

Download the Android APK, open the web app in the browser, or install it to your home screen as a PWA.

Scan for the Android APK

Point your phone camera at the QR code to download the latest APK.

Latest: v1.0.0 · Android APK / Web PWA

Launch web app

Launch in Safari or Chrome and use every feature — builder, voice, rounds and live session. No install required.

iPhone / iPad (Safari)

  1. 1
    Open Rounds & Commands in Safari (not an in-app browser).
  2. 2
    Tap Share, then Add to Home Screen.
  3. 3
    Confirm Add — the icon appears on your home screen.

Android (APK or Chrome)

  1. 1
    Download the APK below, or open the site in Chrome.
  2. 2
    Allow install from this source, or use Chrome’s Install app.
  3. 3
    Launch from the icon — full screen, ready to train.

Frequently asked questions

How do I install the APK on Android?

Download the APK, open it on your phone, and allow installation from unknown sources if prompted.

Does it need an internet connection?

No. Training runs fully offline. Internet is only needed if you choose to sync an account.

Can I use it on iPhone?

Yes — open the web app in Safari and add it to your Home Screen. It then opens full-screen like a native app.

Is there a free plan?

Yes. Free includes core training with built-in commands. Pro and Coach unlock higher limits for custom content and advanced callouts.

Ready to train?

Open the app in your browser or install the Android APK — start free, upgrade when you need more.