Primary iphone
My question is, how to choose a device between my devices, to make it primary not secondary or some?
The term Primary and Secondary are used for Carriers on Dual SIM iPhones, not for the device.
All iPhone devices are primary there is no dependency between them unless you have the same Apple ID on both devices.
- If you do not enable iCloud Photos/Messages the Photos on each device are independent of each other even if the Apple ID is the same
- If you do not enable Message forwarding between devices the devices receive their messages and cannot be seen by the other device even if the Apple ID is the same
- If you use two different email accounts then the email received on one is not seen on the other device even if the Apple ID is the same. The same is true for Notes, Reminders, Calendar etc Excep for iCloud Notes, Reminders and Calendar because the Apple ID is the same