> When Twitter was gathering steam back in 2009-10, it did so because tweeting was done via SMS and not over a proprietary interface. I don't believe this for a second. In 2009-2010, there were already a huge number of smartphones and Twitter clients out there. In fact, that time was probably better for third-party Twitter clients than today. Smartphone growth exploded in 2009-2010, so the idea that "everyone was get…
Their API is not so "free" now -- you need to register your app, always authenticate, and there's no public firehose access any more.