No account. No server. No cookies. Just you, your phone, and an app that minds its own business. cronoWiz is a free PWA that runs entirely on your device — your data never leaves. Ever.
While the rest of the fitness world asks for your email, credit card and blood type before you take a single step, cronoWiz works the other way around.
Zero sign-up
open and go, like your running shoes
Zero backend
no server receives your data, because there is no server. Full stop.
Zero cookies
the only thing we track is your workout, and we only do it on your phone
Zero cloud
data lives in IndexedDB, in your browser. Delete the app and it's gone. Want a backup? You encrypt it yourself with a passphrase.
| label | Google Health Premium | cronoWiz |
|---|---|---|
| Price | $9.99/month ($99.99/year) | Free. Forever. |
| AI Coach | Gemini tells you to sleep more (thanks, Gemini) | Your TSB tells you whether you can push or need to recover — without sending your data to Mountain View |
| Requirements | Pixel Watch or Fitbit + subscription | A browser. Any browser. |
| Your data | On Google's servers, with "science-backed guidance" | On YOUR phone, with math you can verify |
| To deactivate | Cancel the subscription, pray they delete everything | Delete the app. Done. Nothing else to wipe elsewhere. |
Price
Google Health Premium
$9.99/month ($99.99/year)
cronoWiz
Free. Forever.
AI Coach
Google Health Premium
Gemini tells you to sleep more (thanks, Gemini)
cronoWiz
Your TSB tells you whether you can push or need to recover — without sending your data to Mountain View
Requirements
Google Health Premium
Pixel Watch or Fitbit + subscription
cronoWiz
A browser. Any browser.
Your data
Google Health Premium
On Google's servers, with "science-backed guidance"
cronoWiz
On YOUR phone, with math you can verify
To deactivate
Google Health Premium
Cancel the subscription, pray they delete everything
cronoWiz
Delete the app. Done. Nothing else to wipe elsewhere.
Google just renamed Fitbit Premium to "Google Health Premium", bumped the price by $20/year, and added an AI coach that needs your biometric data in the cloud to tell you to take more steps. We give you load monitoring, readiness, HRV and adaptive programs — and the most it knows about you is an optional nickname.
Privacy alone isn't enough. A safe but boring app is like an empty gym with a great alarm system. cronoWiz is also — and above all — fun.
Run through an autumn forest generated in real time, cycle along a beach at sunset, jog through a neon city at night, or dive into an underwater world with bubbles and caustics. Every session is different — terrain is generated procedurally with Perlin noise, trees place themselves, the sun sets while you run.
| label | Zwift | Kinomap | cronoWiz |
|---|---|---|---|
| Price | ~€17.99/month | ~€11.99/month | Free |
| Worlds | Watopia and friends (gorgeous, static) | Real videos (nice, pre-recorded) | Procedural biomes (endless, different every time) |
| Internet required? | Always, mandatory | Mandatory for streaming | No. Works in basements, on mountains, anywhere |
| Companion | Other online users' avatars | None | Your virtual ghost runs with you — or against you |
| Your data | Zwift cloud | Kinomap cloud | Your phone |
| In one word | Cycling MMO | Netflix of fitness | Your private playground |
Price
Zwift
~€17.99/month
Kinomap
~€11.99/month
cronoWiz
Free
Worlds
Zwift
Watopia and friends (gorgeous, static)
Kinomap
Real videos (nice, pre-recorded)
cronoWiz
Procedural biomes (endless, different every time)
Internet required?
Zwift
Always, mandatory
Kinomap
Mandatory for streaming
cronoWiz
No. Works in basements, on mountains, anywhere
Companion
Zwift
Other online users' avatars
Kinomap
None
cronoWiz
Your virtual ghost runs with you — or against you
Your data
Zwift
Zwift cloud
Kinomap
Kinomap cloud
cronoWiz
Your phone
In one word
Zwift
Cycling MMO
Kinomap
Netflix of fitness
cronoWiz
Your private playground
Zwift is great if you want to ride with thousands of strangers and pay almost as much as Netflix. Kinomap is perfect if you love real-route videos. cronoWiz is for those who want worlds generated on the fly, zero latency, zero subscription, and the certainty that no server knows where you're riding.
Levels and XP
every session counts, from warm-up to PR
Daily Ring
close your daily rings (cardio, strength, steps)
Streak
your consecutive-days record, with realistic decay
Achievements
badges for real milestones, not for opening the app
Gems and cosmetics
collect gems in 3D worlds, unlock color variants (winter forest, tropical beach, rainy city…)
Collectible stickers
because adults deserve trading cards too
Real races — no followers, no public leaderboards, no social network in the middle. Just you, an opponent and the road.
Ghost run
pick one of your past runs and a virtual runner sets off at your recorded pace. An arrow points toward the ghost, with the gap in metres and an ahead / behind / tied label.
Repeat-track
a loop you have run before comes back as a faint ghost line on the map, and a voice navigator calls out every turn — “in 80 m, turn right”. The same route is grouped into one circuit in the diary instead of fragmenting into a dozen unrelated entries.
LiveRoom
run live with a friend who is moving now: create a code, they join, and the map splits in two with their dot, their pace and the cadence delta beside yours.
Challenge a friend
pack the route, the pace and the stats into a .cwchallenge file. They open it, accept, and you become their ghost — even from another continent, even on a treadmill. At the end, a verdict: who won, by how many seconds, by how many calories.
Pacer AI
running solo? Pick a target pace and a pacer that never tires sets off down the strip. Beat it, or hold on.
Tempo
turn the run into a countdown. At zero cronoWiz says “Target reached!”, buzzes three times and the timer flips to counting up — because beating your target is the point.
No friends to follow, no leaderboard, no social graph. The race is a file or a direct room between two phones. Full stop.
Got a TV? Got a phone? You've got a gym.
YouTube videos on the big screen
while your phone tracks
3D worlds projected on TV
the forest on a 55-inch hits different
Real-time metrics
HR, pace, distance — all on the TV
The phone stays the brain
sensors, BLE, audio all run there. The TV is just the "cinema".
No Chromecast required. No dongle. No account. Open the browser on the TV, scan, run.
cronoWiz has a research-lab side you don't expect from a free app.
Your phone's camera becomes your form coach. MoveNet analyses your movements frame by frame, all locally.
Put your finger on the camera and cronoWiz measures your heart-rate variability with a full PPG pipeline, in 60 seconds.
A Tone.js synthesizer generates music in real time that adapts to your heart rate. No Spotify, no licensing.
cronoWiz hosts a language model that runs entirely on your device, in WebGPU. No API, no cloud, no prompts shipped to a server: the intelligence is local, like everything else.
On-device LLM via WebLLM
Llama 3.2 1B by default, or Gemma 2 2B as an opt-in “Coach Plus”. Weights live in OPFS and survive updates: you download ~700 MB once, then it’s back in seconds.
“Explain today”
tap the readiness pill and the coach explains in three or four sentences why you are in PUSH, MODERATE or RECOVER today — citing your real numbers (TSB, recent RPE, last session).
Coaching chat
a persistent thread that knows your profile, your load, today’s adaptation and your last 7 sessions. It cites concrete facts instead of inventing them: “nice work on yesterday’s 5K, RPE 7 in 31 minutes”.
All local
the conversation stays on the phone and rides into the encrypted backup. The model weights don’t — they’re regenerable. Not a byte of your training leaves the device.
It’s no substitute for a doctor, a physiotherapist or a personal trainer — and it says so explicitly. Its job is to make your data legible and your plan adaptable, without anyone else seeing it.
cronoWiz isn't a freemium product that locks the useful features behind a paywall.
It isn't a service that gives you the app in exchange for your data.
It isn't a startup hoping to sell you to a bigger company.
It's an app that does what it promises: it helps you train, minds its own business, and asks nothing in return.
works offline, weighs nothing, doesn't bite.