EN · RUWrite to support@prudoapp.com. We answer within a couple of days.
Nowhere by default: your records sit on the device. Syncing between your own devices goes through your iCloud and is switched on by hand. A shared budget does travel through our server, but amounts and names are encrypted on the device with a key that never reaches the server.
Not if syncing or an iCloud backup was on: it comes back on the new device. The shared budget key travels through the iCloud Keychain. If that is gone too, ask the other member for a fresh invite code.
The subscription lives in your Apple account: iOS Settings → your name → Subscriptions. We cannot cancel it for you, and we never charge you ourselves.
In the app: Settings → Profile → Delete account. There is a page about it with the details.
Write to us with the app version (Settings → More → What's new) and what you were doing at the time. A screenshot helps.