Cloud sync

StackUp works entirely on your phone. No account, no server, nothing to sign up for — and that is not a trial, it is how the app is meant to be used.

If you have a second device, or you want your log to survive a lost phone, sign in with Google and it syncs. This is free and there is no subscription for it. Sign-in is available on Android.

Your training log syncs: sessions, sets, exercises, splits and body weight. So do the preferences that belong to you rather than to the phone — your unit, your progression defaults, your rest timer. Your theme stays on the device, because dark mode on a tablet is not a decision about your training.

It is built to survive a gym basement. Nothing waits for a connection: sets are saved on the device the moment you tap them, and syncing catches up whenever there is signal. Being offline is never mistaken for being signed out, and nothing is thrown away because a sync failed.

Signing out leaves your log on the device. Deleting your account removes the server's copy immediately and signs out every device, and your log still stays on the phone, working, just no longer syncing anywhere.

A web app is planned, and that one will be paid. Sync stays free either way — the line is that what you do on the gym floor costs nothing, and the desk half is what a subscription would buy.