Last year, Foursquare was called the break-out mobile app of the conference by more than one tech journalist.

This year, a new contender has appeared - Austin's native Gowalla. And Brightkite is still hanging on to the LBS community,

if only by a thread of loyal users - but they still offer more features than some of their better-known competitors.

Which do you use now? And when your attention is at a premium during one of the year's most popular geek conferences, which app or apps will you use to collect badges, connect with friends, and find out where the party really is?

Gowalla's main weakness might be that they haven't yet developed an Android or Blackberry application. WordPress Bible author Aaron Brazell noted that while many see the iPhone as the "Jesus phone," that doesn't change the fact that "any company who has a business model built around... iPhone is nucking futs."

While many of us use the mobile version of the site and patiently wait for a native app for non-iPhone devices, Foursquare's been our go-to check-in service for quite some time. And their response to us on Twitter suggests they may see themselves as a comfortable incumbent at this point.

Both of the services we've mentioned also have special, built-in incentives for users at SXSW. Gowalla in particular has announced an interesting promotion. For their flagship "Tiki Room" event, the app will "be scattering hundreds of Tiki Room Digital VIP Passes around downtown Austin. The only way to get yours is to check in with Gowalla at other Austin venues and SXSW events."

Last year, Foursquare also had special badges for SXSW, such as "Panel Nerd", "Karaoke RV" and "Porky" (for BBQ lovers, in particular). They even made a custom badge for attendees of Digg's party and Diggnation live show.

And while Brightkite may not have the game mechanics and rewards of other apps, it does give us the ability to upload photos in addition to text when checking into various locations - a tool we've found very handy when screening new venues for ambience.

So, which app or apps will you be using during SXSW? Vote in the poll, and let us know the "why" of your choice in the comments.