justzone2
Zone 2 Training Made Simple
$1.99 · Designed for iPad. Not verified for macOS.
Most apps hold your power. JustZone2 holds your heart rate, so as you get fitter your Zone 2 power climbs. See your aerobic fitness grow, no FTP tests.
Most indoor cycling apps hold your power. JustZone2 holds your heart rate.
Set your zone, start pedalling, and the app takes over. It reads your heart rate every second and continuously adjusts your trainer's resistance to keep you exactly where you meant to be — no watching the numbers, no reaching for the dial halfway through. Just the right effort, for the whole ride.
ADAPTIVE ZONE TARGETING
• A PID controller trims trainer resistance in real time to hold your heart rate in Zone 2
• You choose where you ride within Zone 2 — the upper part by default, where steady Zone 2 rides are meant to sit
• Handles cardiac drift automatically — as you tire and your heart rate climbs, the power eases back to match
• Optional warm-up and cool-down phases
• Prefer to ride to a number? Run it as a straightforward fixed-power ERG session instead
AND, WHEN YOU WANT IT, INTERVALS
• An optional Interval Builder for your hard days, switched on in Settings
• Set the number of intervals, their length and power, and the recovery power in between
• Ride in sets, with a longer recovery between them, for sessions like Rønnestad's 3 × 13 × 30/15s
• Ridden in ERG mode, with a countdown to every interval and the session's shape on screen
• See each session's weighted average power, a better guide to how hard it will feel than plain average power
• Interval rides upload to Strava under their own name and stay out of your Zone 2 progress charts
WORKS WITH YOUR GEAR
• Any smart trainer supporting the FTMS Bluetooth standard, including the Wahoo KICKR range
• Heart rate from an Apple Watch, a Bluetooth chest strap, an optical arm band, or AirPods Pro 3
• Universal — iPhone, iPad and Apple Watch, with a Watch complication for a glance mid-ride
YOUR DATA, WHERE YOU WANT IT
• One-tap upload to Strava with power, heart rate, cadence, distance and calories
• Saves to Apple Health as a full workout
• Live Activity keeps your stats on the Lock Screen and in the Dynamic Island
• Workout history with charts, so you can watch the aerobic base actually build
BUILT TO GET OUT OF THE WAY
• Large, readable metrics you can see from the bars
• No ads, no upsells, nothing to sign up for
• No subscription — one purchase, yours for good
• Interrupted mid-session? It picks up exactly where you left off
WHY ZONE 2
Easy aerobic work is what builds the engine: more mitochondria, more capillaries, better fat metabolism, and a foundation broad enough to carry everything you stack on top. It is the bulk of what elite endurance athletes actually do all year.
Understanding that has never been the hard part. Holding the discipline to ride easy enough, for long enough, is the hard part — and that is precisely the bit JustZone2 takes off your hands.
MADE FOR
• Cyclists building an aerobic base through the winter
• Athletes who want recovery days to stay genuinely easy
• Anyone after structured indoor training without a games engine attached
REQUIREMENTS
A smart trainer that supports FTMS, and a heart-rate source — Apple Watch, chest strap, optical arm band or AirPods Pro 3.
Set your zone once. Every ride after that, just press start.
• Fixed: with Warm Up on, Zone 2 sessions now rise to your target power when the warm-up ends. In versions 1.0.2 and 1.0.3 they could stay at the warm-up power.
• Interval Builder: ride in sets. Repeat a block of intervals with a longer recovery between sets, for sessions like Rønnestad's 3 × 13 × 30/15s.
• New interval sessions start with a 5-minute warm-up.
• When a session finishes, your trainer eases to half your final power for the cool-down.
The developer, GEORGE GAIMES WHICHELOE, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- GEORGE GAIMES WHICHELOE
- Size
- 6.2 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 26.0 or later.
- iPhone
Requires iOS 26.0 or later. - iPad
Requires iPadOS 26.0 or later. - Mac
Requires macOS 26.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 26.0 or later. - Apple Watch
Requires watchOS 26.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © @ 2026 George Whicheloe
