Can others on a shared photo stream add photos to the shared photo stream?
Not at the present time. Only the person creating the shared photo stream can add and delete photos.
If you have updated to iOS 7, then allowing multiple people to share to the same stream is possible.
Go into your stream in the Photos app, and tap "People" at the bottom. From that screen you can toggle the switch that will allow subscribers to post to your photo stream.
Does anyone know why I can't get my photos to share from my iPhone to my new iPad ? I checked my Settings and everything seems to be in order.
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