For Polar Loop and iPhone

Find your even keel.

Keely reads your Polar Loop and tells you how recovered you are, how hard to go, and how you’re handling the day. Every number is explained, and nothing is made up.

Coming soonon the App Store Need a Polar Loop?
Keely’s Today screen: Recovery 79 percent, Primed, with HRV 70 ms and resting heart rate 49 bpm, both against their normal range.
Keely’s Recovery screen: the score and what moved it, from HRV and resting heart rate to sleep and breathing rate.
Keely’s Sleep screen: 7 hours 20 minutes asleep, the night story with stages and stress, and time in each stage.
Keely’s Stress screen: stress 23, Calm, live from the Loop, with today’s timeline and time in each level.
Keely’s Training screen: Load against today’s target range, the week’s balance and the intensity mix.

Every morning

Every number, explained.

When you wake, Keely scores last night against your own 30-night normal. HRV and resting heart rate carry most of the weight, with sleep, breathing rate and skin temperature alongside.

Tap the score to see what moved it: helping, holding back or normal.

  • Primed 67–100
  • Balanced 34–66
  • Restore 0–33

Last night

Your night, as a story.

Sleep stages with stress, heart rate, HRV and breathing on one timeline. See time asleep against your need, how consistent your schedule is, and when to turn the lights out tonight.

  • Deep
  • REM
  • Light
  • Awake

Right now

Stress as it happens.

With your Loop connected and Keely open, stress updates live from your heart rate and beat-to-beat variability, scored from 0 to 100 against your own calm.

It’s only scored while you’re still, so a workout never counts as stress. Moments show when it stood out, day and night.

  • Calm 0–25
  • Mild 26–50
  • Elevated 51–75
  • High 76–100

This week

A target that moves with you.

Load counts every minute by its heart-rate zone. It’s linear and has no ceiling: twice the work is twice the Load.

Each morning brings a target range set by your Recovery and your last four weeks, and Balance shows whether you’re maintaining, building or overreaching.

  • Z1
  • Z2
  • Z3
  • Z4
  • Z5

Calm by design

Quiet until it matters.

Keely is made to be read half awake in a dark bedroom. It says what it knows, shows what it doesn’t, and keeps its voice down.

Gaps stay gaps.

Missing data is shown as missing, activity is never scored as stress, and an older reading shows its time.

Every score shows its work.

Each number keeps its inputs, so you can always see what moved it and by how much.

Cool is normal. Warm asks.

Color means good or bad, not up or down, and it always comes with a word or an arrow.

No ceiling on effort.

Load is linear: twice the work is twice the Load. No gauge gets harder to fill the higher you go.

Private by default

Your heartbeat stays on your iPhone.

Keely computes every score on your phone. Only your account, profile, band and daily summaries are backed up, so a new iPhone can pick up where you left off.

Every heartbeat, day and night
On this iPhoneYour raw heart data stays on your phone.
Daily scores and summaries
Your accountBacked up for a new iPhone.
Which screens you open
AnonymousNever health data. Off in Settings.
Ads and data sales
NoneNo ads, and your data is never sold.
The Loop has no screen. Its lights and Keely are its whole voice.

What you need

Your Loop, understood.

Pair your Polar Loop once. Keely syncs, reads your night and learns your normal over your first few nights, and the scores firm up as it does.

  • A Polar LoopKeely talks to it directly over Bluetooth, instead of the Polar Flow app. Already on Flow? Keely walks you through the move.
  • An iPhoneWith iOS 26 or later.
Get a Polar Loop

We may earn a commission when you buy through this link. As an Amazon Associate, Metrica Fit earns from qualifying purchases. Keely is an independent app and isn’t affiliated with or endorsed by Polar Electro.

A keel is the spine under a boat. It carries the ballast that pulls the hull upright after every gust.

Keely does that job for a body. It reads what the day put on you and what the night gave back, and helps you stay level.

Coming soonon the App Store Need a Polar Loop?