Heart-rate monitors
Pairing one
Go to Settings → Heart rate → Pair a monitor. Put the monitor on first: chest straps only appear once they can feel a heartbeat, and watches and bands only appear once they've been told to share. Tap your device in the Found list when it shows up.
Nothing showing up?
Watches and bands are invisible to other apps until you switch sharing on, and nothing tells you that. The setting is in the band's own app:
- Fitbit Air — "Share heart rate", in the Google Health app under Connections.
- Fitbit Charge 6 — "HR on Equipment", from the clock face.
- Pixel Watch — "Connected Fitness", in quick settings.
- Garmin — "Broadcast heart rate".
Chest straps wake up on their own once they feel a heartbeat. Apple Watch does not share its heart rate with other apps at all — that's an Apple restriction, not a Runt one, and the only way round it is a companion app on the watch itself, which is on our list but is not in this version.
What it does with your heart rate
On easy, long and tempo runs, Runt coaches off effort instead of pace. The leash is loose on purpose: roughly three-quarters of your maximum, about a minute of grace before it says anything, and it stays quiet going uphill. It asks your age to estimate your maximum, and a hard effort corrects that estimate on its own. It's a casual running app and the margins are deliberately big — we're not claiming laboratory accuracy, and you don't need it.
The plan
How three questions pick a plan
You say how far you want to get, how many days a week you can run, and roughly where you're starting from. Those answers land you on one of 97 plans that already exist, so you see the whole thing — every week, every session — before you start. If you've given it a race distance and a date, the plan is fitted to the weeks you actually have.
How the plan changes
After each run you tap easy, fine or brutal, and the app also weighs how the run itself went. When two signals agree, it offers to move you. The rules are deliberately cautious: it will move you down more readily than up, it won't offer more than one change a week, and if you decline a direction it stops suggesting it for a fortnight. Beginners get "skip a rung" or "repeat the week" instead. Nothing changes without you agreeing to it.
Changing the days, or swapping a session
On the start screen each session has Which day? — a weekday label you put on it — and Swap it, which offers another session from the same plan of the same hardness and roughly the same length. Race day is never swapped. Swaps clear when the week moves on; the days you pinned carry forward.
Voices and language
Why is it so sweary?
Because a coach that talks like a pamphlet is a coach you stop listening to in week two. The packs are written the way the films they're winking at actually sound.
Clean mode
Settings → Voice → Clean mode drops the sweary lines. Every cue still says something — you don't get silence where the joke was, you get a different line. It's a whole second recording, not a bleep.
Changing voice
Settings → Voice. Every pack is already inside the app, so switching is instant and works with no signal. You can change between runs as often as you like.
During a run
Can I lock the screen and pocket the phone?
Yes — that's the intended way to use it. Runt keeps measuring and keeps talking with the screen off and the phone in a pocket. You only touch the app to start and to finish.
Music
Play music from whatever app you like and start the run. Runt ducks it for each cue and hands it straight back. If you'd rather hear a cue on demand before you set off, there's a "Hear a line over your music" row in Settings to check the balance.
What if the app closes mid-run?
Force-quitting ends the run. iOS can also shut a backgrounded app down on its own if the phone comes under severe memory pressure — rare, but possible on a long run with a lot else open — and in this version that loses the run in progress. Being able to resume an interrupted run is the next thing being built. If you're doing something long and it matters, keep other heavy apps closed.
"GPS weak"
Runt says this only when it genuinely can't trust the positions it's getting — under trees, between tall buildings, in the first minute before the fix settles. It keeps timing and picks the measurement back up when the signal returns. Standing still at a red light is not treated as a slow kilometre.
Health, units and data
Health
Runt asks the first time a run finishes, and writes each finished run to Apple Health as a workout — distance, duration, route and heart rate. It only ever writes; it never reads anything from Health. Turn it off in Settings → Health, or in iOS Settings under Health → Data Access & Devices.
Miles instead of kilometres
Settings → Units. Kilometres are the heart of the app; switching changes what's on screen, but the voice still counts in kilometres, because that's how every line was recorded.
Getting your runs out, or deleting them
Runs saved to Health can be exported from the Health app like any other workout. Everything else lives only in Runt on your phone, and deleting the app deletes it. There's no cloud copy and no account, so there's nothing for us to delete at our end — see the privacy policy.
Starting the plan again
Settings → Plan lets you re-answer the questions. Your finished runs stay; only the plan is rebuilt.
Still stuck
runt@youbettarun.com. Genuinely, a person reads it.