The reason is its whole design: thousands of riders in shared, hand-built worlds, which means a server, an account, and a monthly bill. If what you actually want is for the treadmill hour to stop feeling like an hour on a treadmill, that machinery is a lot of overhead for the benefit.
cronoWiz generates the world instead of hosting it. Terrain is built procedurally with Perlin noise, so a forest, a beach at sunset, a neon city at night or an underwater biome are different every session rather than a fixed course you memorise. The scene moves with your real pace, the day drifts from dawn to night, and forks in the route are yours to choose.
It runs on the phone, or on a television with the phone as the remote and the brain. Nothing is streamed, so there is no buffering and no connection required — and no subscription, because there is no server to pay for.
-
Worlds generated, not streamed
procedural terrain, different every time, with no video to buffer.
-
On the TV, without a dongle
open the browser on the television, scan a code, and the phone drives it.
-
It follows your real effort
the scene moves with your actual pace and heart rate, not a fixed video.
-
No subscription, no account
free, and offline once loaded.
What the subscription actually buys
Zwift’s monthly fee is not a markup on a piece of software — it pays for something real. Thousands of riders in one shared, hand-built world need servers running continuously, a persistent account tied to your progress, and the connection to keep it in sync. Racing an actual stranger in real time is not a feature you can move onto a phone.
So the question is whether that is what you want. If you are training for group racing and the other riders are the reason you get on the bike, pay for it — nothing here replaces it. If what you want is for the treadmill hour to stop feeling like an hour on a treadmill, you are paying for a great deal of machinery to solve a problem that does not need it.
cronoWiz generates the world rather than hosting it. The terrain is built procedurally with Perlin noise, so a forest, a beach at sunset, a neon city at night or an underwater biome come out different every session instead of being a fixed course you memorise by week three. The scene moves with your real pace and heart rate, the light drifts from dawn to night as you go, and the forks in the route are yours. Nothing is streamed, so there is no buffering, no connection needed after the first load, and no subscription, because there is no server to pay for.
Getting it onto the television
A phone-sized world works, but the effect is much better on a big screen, and it does not need a dongle or an app store. Open the browser on the television — most smart TVs from the last few years have one that is good enough — go to cronoWiz, and scan the code it shows with your phone. From then on the phone is the remote and the brain: it holds the session, talks to the heart-rate strap and the treadmill, and drives what the TV renders.
If the television’s browser is too old or too slow, casting the phone screen works as a fallback and costs a little smoothness. Either way the 3D itself is rendered on the device, so the quality depends on the phone rather than on the connection.
On first run cronoWiz checks the device and picks a quality level, and steps it down if the scene starts struggling partway through a long session — a dropping frame rate in minute forty is a worse experience than slightly simpler trees from the start. A treadmill or bike that speaks FTMS over Bluetooth can be read and controlled directly, so the program sets speed and incline and the terrain you see matches the resistance you feel.
Free. Private. Yours.
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.
The questions people actually ask
Can I ride with other people?
Live with one person at a time, through a direct room you open with a code. There is no shared persistent world with strangers — that is precisely the part that would require servers and a subscription.
Does it work with a smart trainer?
Treadmills and bikes that speak FTMS over Bluetooth can be read and controlled, so speed and incline follow the program. Heart-rate straps connect the same way.
What hardware do I need for the 3D?
A reasonably recent phone. cronoWiz checks the device on first run and picks a quality level, and steps it down if the scene starts struggling during a long session.