My sister recently got a new iPhone and I have taken her old one as mine is broken. I put my SIM card in and signed out of all of her accounts but she can view on my current messages, photos and Internet browser from her new phone. How do I fix this?
Your sister needs to follow these directions before giving the phone to you:
What to do before selling or giving away your iPhone, iPad, or iPod touch - Apple Support
Not sure what you mean by "signed out of all her accounts", but her old phone is still connected to her iCloud account, with her Apple ID.
Help with switching over to my sisters old phone
