iPhone/iPod touch: Gist, an inbox aggregation webapp that sorts your email, RSS, and other feeds based on the frequency and importance of contacts, has released a free iPhone app that brings the same powers to the small screen.
If our review of Gist's webapp features intrigued the part of your mind that's overwhelmed with random emails from anyone who bothers to hit send, Gist delivers much the same experience on an iPhone. You can browse contacts to see what they've been up to, get your email delivered with the contacts Gist has deemed most important on top, and read your Twitter or blog feeds with the same kinds of filters on.
The drawbacks for this version are the lack of tie-in to the native calendar or email apps, as well as the necessity of tweaking your filter settings, and signing up for an account in the first place, only on the Gist site. Still, if you're looking for a different window on what's happening around your networks and contacts, Gist is worth trying out. It's free to use, and requires a sign-up at the Gist site to use.