Intervalla 1.2: Train With Your Screen Locked
Version 1.2 adds background audio, live heart rate sparkline, post-workout summary, shareable workouts, and lock controls. Put your phone away and train.
A few weeks ago we wrote about what was coming next. Most of that list has now shipped.
Version 1.2 is live on iOS and the web app. Here is what changed.
Background Audio
This was the most requested fix, and the one we are most glad to have working properly.
Audio cues — countdown beeps, phase transitions, the completion melody — now play reliably when your screen is locked or the app is in the background. Your Bluetooth heart rate monitor stays connected too.
That matters because most people do not stare at their phone during a workout. You put it on a bench, in a pocket, or on an armband. The screen turns off. And until now, the audio would eventually stop or get out of sync.
The fix was not trivial. On iOS, web audio runs in a sandboxed process that the operating system can suspend. We ended up bypassing the web audio layer entirely and built a native audio scheduler that uses the device's hardware clock for timing. The result is that cues land exactly where they should, even minutes after the screen goes dark.
Heart Rate Mode
If you connect a heart rate monitor, you can now switch to HR mode during a workout.
Instead of the countdown timer being the main element, HR mode puts a live sparkline front and center. It plots your BPM over time so you can see the work and rest pattern as it builds. The timer is still visible, just smaller.
This is useful for sessions where effort control matters more than watching seconds tick down. Steady-state conditioning, active recovery, aerobic base work — that kind of thing.
Post-Workout Summary
When a workout ends with a heart rate monitor connected, you now get a summary screen showing:
- Average, max, and minimum BPM
- Time spent in each heart rate zone
- A full session sparkline with work and rest phases marked
It is a quick snapshot of what the session actually looked like, not just how long it took.
Share Workouts
You can now share any workout as a link. Custom intervals, a specific Tabata setup, whatever you have configured — tap share, send the link, and anyone with Intervalla can import it with one tap.
This is handy for coaches, training partners, or anyone who would rather send a link than explain an interval structure over text.
Lock Controls
A small but useful addition. Tap the lock icon during a workout and the controls are disabled until you unlock them. No more accidentally pausing a set because your sleeve brushed the screen.
What Is Next
We are still working through the longer-term ideas from the roadmap post. Heart rate zone mode, workout chaining, and workout history are all still on the list.
If there is something you want from Intervalla, reach out through the contact page. A lot of what ended up in this release started as a message from someone using the app.