how do i add another device to find my phone
You have to use the same Apple ID on both devices for iCloud. However, if you have an iPhone 3G, you can't, as it does not support iCloud.
Does this make both phones sync all other things, email,music,pics and laptop or can that be edited
You can sync whatever you like to each device. iTunes will keep track of everything, by device, including separate backups.
So to round up, if I have a 3 it does not support iCloud , but if both are 4 I can put both on the same sign in details .
And I can still select what details I want shared with each phone individually.
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