The Gowalla app for iPhone has been updated to make it compatible with the iPhone 4’s new Retina Display. The result? Some very nice eye candy, especially on Gowalla’s pins and stamps. The higher-res display brings out some nice detail and all the text and mapping in the app looks much nicer. Some older pins (like ones related to SXSW Interactive) look a little jagged around the edges, but the ones that take advantage fo the new display really pop.

The update also is said to improve location detection (which seems to have been a problem lately), adds multitasking (tracking locations in the background) and fast-app switching. It also adds French, German, Spanish, Japanese or Arabic languages to the app.

Outside of the iPhone universe, Gowalla’s Android app now includes search, photos and commends, and an updated design.

But perhaps the biggest addition it a dedicated BlackBerry app that debuted last month. Mutual Mobile, an Austin company, helped develop the app, which is currently out in a beta version.

In an e-mail update today, the company said it now has 350,000 users (or as they call them, “Passport holders”).

After getting lots of attention at South by Southwest Interactive, Gowalla has been releasing frequent app updates, has released an iPad version and has been putting together deals with media companies, including the American-Statesman.

Original article features on Austin 360