Log your set. Put your phone down. Lift.

Smart Sets automates everything between your sets: the rest timer, the next set pre-fill, the haptic reminder. Stay focused on what matters.

Free to download. Android beta: join the waitlist

ZON live strength session with sets, reps, RPE and a rest timer
  • Auto-start rest timer on every logged set, no manual trigger

  • Smart pre-fill, the next set inherits weight and reps from the previous one

  • Haptic end-of-rest reminder on your phone or your Apple Watch

The problem it solves
Between every set, you unlock your phone, find where you were, enter the weight manually and launch a separate timer. You spend as much time on the app as you do under the bar.

The problem nobody wants to admit

Most fitness apps ask too much of you during a session. Logging a set means: find the exercise, enter weight, enter reps, confirm, start a timer, wait, start again. That's cognitive work during a moment that should be reserved for physical focus.

Smart Sets reduces every interaction to a tap or two.

What happens the moment you log a set

1. The rest timer starts automatically. Nothing to configure. The moment you confirm a set, the countdown begins, using the rest defined in your program or the one you set once.

2. The screen gets out of the way. You see the timer, the pre-filled next set, and nothing else. ZON doesn't ask for anything until rest is over.

3. Your wrist tells you when to go. At the end of rest, a haptic buzz arrives on your iPhone or Apple Watch. Look at the bar, not your phone. The timer also follows you on the Lock Screen through Live Activity.

4. Your next set is ready. Weight and reps from the previous set are pre-filled. Same load? Confirm in one tap. Going up or down? Adjust in seconds. Add RPE if you track it.

Rest timers per exercise

Smart Sets doesn't use a single global timer. Heavy squats can get 3 minutes and curls 90 seconds. ZON applies the right rest for the current exercise, and you can add or remove time on the fly.

Result: denser sessions

By removing the micro-friction between sets, Smart Sets keeps your rest honest and your focus on the work. Same sets, same intensity, less time lost to your phone.


In the ZON app on iPhone. Android is in beta: join the waitlist at justzon.com/android-waitlist.

Your next session starts here.

Download ZON for free on the App Store. On Android? Join the beta waitlist.