What are uses of Google Plus apart from social networking? I mean, like photo syncing on Android to convert into high-definition images?
Collect data on its members.
That's about it. You can upload your Android photos to Google+ to be automatically backed up, You need a profile set up to have your picture appear in Google search results if you're an author, like this, for example.
Meeting new people? Following pages if you don't want to use Facebook? The Hangouts integration is useful, too.