Iphone apps being used but not by me!

They would only see them if Macdonald’s and Subways servers have been exploited. Your account with them is under their security and control, not your device. And if someone is using those apps with your account ID, then they already must know your current password to be able to do that. So changing the passwords is the only way to stop them.

You should also contact support at both the McDonalds and Subways web sites and report that your account was compromised, and alert your bank about that for whatever payment you have tied to those two accounts.

Your phone has not been hacked, but your online accounts for those services likely have been. You need to change the password you use with those payment apps. Login to your McDonalds and Subway accounts and change those passwords there.

BTW, this is what happens most times people think their iPhone has been hacked - yet it has nothing to do with your iPhone itself. It has to do with online service accounts you use through Apps on the iPhone. It is those online accounts that have been hacked.

If you have the option to rename your accounts do that as well. Via "forgot my password" they will be able to abuse your account in the future by resetting your new password if your account ID is an email address.