This usually happens after an update or may be after you’ve restored your iPhone. Even otherwise, let’s check this out: your iPhone keeps asking for the Apple ID password. There’s nothing downloading, there are no wrong passwords, there’s no problem with your account. And yet you keep getting this pop-up which makes life unbearable with the iPhone.
It’s usually a case of failed downloads which aren’t directly visible on the homescreen. Sometimes it’s a problem with your account settings: either in iCloud or iMessage/FaceTime or in the App Store.
Let’s try to fix this as smoothly as possible. If it doesn’t look smooth, my apologies.
How Do I Fix This Issue: iPhone Keeps Asking for Apple ID password!
The first thing you do in such a circumstance is reboot your iPhone. Optionally, you can also try resetting the iPhone without erasing the data. (Settings -> General -> Reset -> Reset Settings)
In all probability, you’ve tried this. If the iPhone still keeps asking for the Apple ID password, head over to the next one.
2. Check Updates/Purchased Apps/App Store/iTunes Store
The first thing you do is open the App Store and check your Purchased Apps history. The Updates section shows you apps that are ready for updates but above it, there’s the purchased apps section. Check to make sure there’s nothing hanging in a failed download or something. These may/may not show up on your homescreen so this is the only way to check if there’s an app hanging midway in a download that’s failing.
Next up, open your account settings in the iTunes & App Store (Settings -> iTunes & App Store) and try logging out of your Apple ID and then log in again. This might solve your problem or give you a hint about where the problem could be.
When you do this, if you find that your are unable to login to your Apple ID, this means there’s something wrong with your Apple ID or the password. Try a password reset from your Mac/PC and then come back to your iPhone/iPad again and login with the reset password.
Did you check your iCloud account? Is it configured correctly? Try turning off iCloud by deleting your account. (take a backup both in iCloud and over iTunes before you do this).
When you get to Settings -> iCloud, tap on the Account field and erase and retype the password for your Apple ID. Click on Done afterwards and see if this fixes the issue.
If things are still the same, you’re probably going to have to check out iMessage and FaceTime under Settings. Both iMessage and FaceTime use your Apple ID even if you’re not using these services (but have them turned on). There might be some problem with the account information, or activation.
Try turning these off (I know it can be cranky to get them back ON but you’ll have to try it!). If it works, then Voila! You’ve fixed the source of the issue. Re-activate iMessage and FaceTime with your correct Apple ID and password.
4. What if nothing works?
Are you sure iTunes Store isn’t trying to download something which is on a download-loop or failing repeatedly? Check it out by heading over to the iTunes Store on your iPhone. If there are any pending tracks that are stuck, remove them, restart your iPhone and check if this fixes the problem.
Also, if this fails to solve things, you’ll just have to restore your iPhone from an iCloud/iTunes backup. A clean restore usually helps reset all things and throws away the problems. You’ve got the data backed up anyway so if it helps, why not just do it and get rid of the issue?