Pebblett wrote:
Hi. No it wasn’t his phone: mine from new. I could update as normal till a couple of weeks ago and no I’ve not downloaded any apps on my phone under his details.
If you set up the iPhone from a backup of a previous one, it could have apps form a previous phone that were downloaded with his Apple ID. The fact remains these Apps where downloaded with his account which is why they are requesting it now.
If I reinstall all apps (currently doing that, it’ll take a while), will the App Store then show my email address?
For the Apps in question, yes. For the general App Store the Apple ID being used is defined in Settings ➜ Account ➜ Media & Purchases. If your Apple Account is not logged in there then deleting the app and re-downloading them will do nothing as the apps would continue to be tied to whatever Apple ID is logged in there.
A few apps are saying I’ll delete all data if I delete the app (Facebook being one), do I just go ahead?
Yes. Facebook will restore everything once you log back in.
What about the phone’s own apps: Mail, Photos etc? Ok to delete and reinstall those?
Those should not be tied to another Apple ID, since they aren't usually downloaded from the store to begin with, and those get updated with the OS, so no need to delete them. But yes, it's fine to delete those apps also, and re-download them from App Store for the ones that allow this. Not all of them do.