Lifestreaming apps, which combine and track multiple social network accounts, are popping up like spring flowers in my inbox. The best, like RoamBi, rethink the way information is presented on an iPhone rather than a desktop, laptop, or BlackBerry.

Zensify, an iPhone app available as a free preview in the App Store, stands out for the personal tag cloud it creates from Facebook, Twitter and other social sites.

The cloud, shown in the screenshot above, is like Twitter’s trending topics list with two exceptions. First, instead of showing what everyone on the Internet is talking about, Zensify plots the trends only in your friends’ updates, and only on networks for which you’ve logged in via Zensify.

Second, Zensify’s tag cloud lets you quickly grasp the relevant size of individual trends. Compare my tag cloud here to Mike Butcher’s screenshot at TechCrunch.

The goal, says co-founder Bastian Lehman, is to make it easy to “update, discover and keep track of your friends’ pictures, videos and comments across the Web” from an iPhone.

Networks currently supported are Facebook, Twitter, YouTube, Flickr, Digg, del.icio.us, Photobucket, and 12seconds. Lehmann says more are on the way.

In July, Zensify is scheduled to go from preview to completed product. iPhone users will be able to choose either a free version with ads delivered by AdMob or a similar service, or a premium version with no ads and extra features.

Zensify is a startup in London. The company has eleven employees and one blog. Zensify’s sole funding is an undisclosed amount from Ipex Capital.

Founders Chris Convey, Tom Campbell, Richard Peel and Lehmann claim to have years of experience in mobile applications. Lehmann said in an email that he previously worked for Refresh Mobile (now Mippin), and mobile marketing firm 12snap.

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