I need to change phone

This was very confusing to me. I'm a mobile user so I don't have to worry about my phone on the same table. I have a Samsung Galaxy S3, an iPhone 3, and an iPhone 5. If I want to check my email, I open my calendar app and choose 'Email' and tap 'Change.' I'm on my iPhone, and when I take the picture I get an error saying that a photo was already uploaded. It didn't take that long