Support
Write to engr.kamalnasir@gmail.com. Say which iPhone and which iOS version, and what you expected to happen.
An Apple Music track will not analyze
Streaming tracks from Apple Music are protected and cannot be decoded by any app. That is not a bug and there is no setting that changes it. Quint works on files you own, on files shared into it from another app, and on anything you can hear through a speaker. A track that is in your library but not downloaded also cannot be read until it is on the device.
The key looks wrong
Key detection is an estimate. Quint shows how much of the track stays in the key it names, and a low figure there usually means the track changes key rather than that the reading failed. A modal track, a live take or a heavily processed mix can all read as a neighbouring key. The harmonic code is the number to mix by; the letter is the number to argue about.
Reading from a speaker gives a different answer
Twenty seconds captured from a room carries the room: reflections, the speaker's own response and anything else making noise. Hold the phone closer to the source, keep the room quiet, and give it the full twenty seconds. A file you own will always read better than a room.
Sharing a file into Quint
Use the share sheet from Files, Voice Memos or anywhere else that shares audio, and pick Quint. The file is copied into a private inbox, analyzed, and the copy is removed. Your original is untouched and stays where it was.
Loudness does not match my DAW
Check that you are comparing the same thing. Integrated loudness is measured over the whole track and gated per ITU-R BS.1770; a short or very quiet passage has no meaningful integrated value. True peak is measured with oversampling and will read higher than a sample peak meter. The targets table names the page each platform figure was read from and the date it was checked.
Getting your readings out
Settings, then Backup, then Export. The file holds your whole crate and every set, and Import reads it back. A set can also be exported as a CSV from the set itself.
Restoring a purchase
Settings, then Restore purchases. Restores run against the Apple Account signed in on the device, so if you bought Pro with a different account, sign in with that one first.
Deleting everything
Deleting the app deletes the crate, the sets and any kept recordings, because they live nowhere else. Export first if you want to keep them. There is no account to close and nothing held on a server, because there is no server.
More about Quint: its page on madebykamal.app.