I've written previously on DailyFinance about Gowalla, the pretty check-in also-ran that was the second-largest mobile social network after Foursquare. Austin, Texas-based Gowalla hasn't been growing as quickly as its dominant Big Apple-based competitor, but with its new Gowalla 3 version, it could reverse that equation.

The company astutely changed its game plan by designing Gowalla 3 to allow users to check in on multiple social networks from its dashboard and to track their friends across multiple social networks. The Check.in app had tried to do this a while back, but it didn't take off, in part because its user interface wasn't quite right. Gowalla, though, is a masterful user-interface company and has made it much easier to manage multinetwork check-ins: It's an antidote to check-in fatigue.

How Will Foursquare React?

Whether archrival Foursquare will continue to allow Gowalla to pull data out of its API 9 (application programming interface) to allow Gowalla users to easily check-in on Foursquare or watch FourSquare users is an open question. Version 3 could elevate Gowalla to an aggregator, letting it piggyback on Foursquare's popularity, which would naturally upset Foursquare.

Then again, Foursquare could easily pull off a similar move. Neither Facebook nor Twitter, both of which are integrated into Gowalla 3, are likely to object: Both have tolerated outside firms pulling in their check-in data, and Twitter has a massive ecosystem of third-party clients that carry a big chunk of the traffic on the short-message social network.

Multiple check-in isn't the only neat feature Gowalla has added in version 3. Another is Notes, which lets users leave notes attached to specific locations for other users or for themselves. Version 3's bookmarks are similar to bookmarking sites on the Web, but in this case it lets users curate lists of places more easily. And its picture integration has been improved. (No surprise -- Gowalla has always handled the graphical stuff better than Foursquare.)

At present, this is only an iPhone app, but Gowalla will certainly hustle out an Android version soon.

Whether Gowalla 3 will take market share away from Foursquare is tough to predict: Momentum in social-networking tools is hard to overcome. Regardless, it's certainly a whole lot more interesting than the last version of Gowalla. It also appears that Gowalla is going to be pushing harder into discount offerings. Another good move.