Secure iPhone data whilst getting repaired
My first instinct was to backup the iPhone, factory reset and wipe it and then hand it over to the repair shop. Once received from service, factory reset and wipe again, and restore the data from backup.


This is an extremely safe approach. While the concerns raised in the question are well-researched and fairly obvious, this approach may involve a lot of work &amp; time from your side. If I were in the situation, I'd do the same to remain extra cautious.

iOS is a fairly safe and robust platform and the likelihood of getting unintended data transfers (to and from) are very low when the device is locked. The likelihood can be further strengthened manyfold just by turning off the iPhone or restarting and not unlocking it (even once).

With recent releases of iOS 11.4.1, Apple has further strengthened the device security by introducing a feature called iOS Restricted Mode, which when enabled (it is enabled by default) restricts unauthorised access over the device Lighting Port. You should update the iPhone to iOS 11.4.1 and turn on the setting.

Learn more about iOS Restricted more here:


Using USB accessories with iOS 11.4.1 and later
Apple’s USB Restricted Mode: how to use your iPhone’s latest security feature



Last but not the least, It will be a  good idea to learn about the credibility of the repair shop before handing over your device.