Short version: nothing leaves your device. Longer version below.
Everything you log — jobs, tools, calibration dates, hazmat, notes, time entries — is stored locally in the app's sandbox. It does not leave the device unless you export it explicitly (PDF, AirDrop, Files).
FRO does not make network requests during normal use. It works fully offline. The only outbound traffic is whatever iOS itself does when you tap an App Store link or share via the system share sheet — that's iOS, not FRO.
When you export a job (.frojob), tool kit (.frotool), or PDF, you choose the destination. FRO does not auto-upload anywhere. Once a file leaves the app via AirDrop, Mail, Files, or another share target, that destination's privacy applies, not ours.
FRO is intended for working aircraft mechanics. It is not directed at children and does not knowingly collect data from anyone, regardless of age, because it does not collect data.
If the data posture ever changes — it isn't planned to — this page will be updated and the change noted in the App Store release notes. The current version of FRO does not collect or transmit data.
Questions: see Support.