An important point for social interaction designers 

The term “social network” is of course synonymous with online networks like Facebook. But think about what you’re actual social life is like for a second. Are you really closest to the people whose items you “like” the most on Facebook? What about the people you @reply or retweet on Twitter? The people you reblog the most on Tumblr? If you’re anything like me, probably not. Instead, the best indicator of who I actually interact with socially the most in real life are the calls I make and the texts I send — it’s all mobile interaction.

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APIs for Android and the iPhone give you access to contact list information to varying degrees. But most startups are still approaching that idea as a secondary tactic after they’ve hooked in your social graph through Facebook or Twitter. But I think we may start to see some that go right to the heart of your contacts on your mobile device.

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But imagine if Apple built social tools right into your Contacts app? Maybe it would start with short status updates (maybe this would even pull in tweets), and then it would move to something like instant messaging. Then imagine if they did something with location? All of this would be opt-in, of course, but it could be very powerful.

Via: The Real Social Network: Your Mobile Contacts