Europe’s answer to the location-based services craze, Rummble, is seeking a bit of peace amid the competition for users to exclusively check-in and share their locations with a single app.

To do so, it’s aggregating check-ins from other services that are publicly shared on Twitter through its mobile apps. That way, users can see where their friends are regardless of which service they use to temporarily share their whereabouts. The company will parse natural language on Twitter like “I’m having a drink in the W Hotel Bar” to derive locations, and it will also pull check-ins that are tweeted from services like Gowalla and Foursquare. (See the bottom photo from Tremors, a special Rummble site that lists the busiest places according to tweets.)

It’s not a perfect solution, considering that many people don’t publish their check-ins from these apps on Twitter. But Rummble, which says it has 100,000 active users, believes it will eventually be able to add full real-time data feeds, or firehoses, from other location startups. SocialGreat and SimpleGeo recently became among the first services to pull in data from Foursquare’s firehose, a special anonymized feed of check-ins.

“People will still check-in with whatever service they prefer. They don’t have to switch from Foursquare or Gowalla,” said Alex Housley, Rummble’s vice president of business. “We’re more of a reviewing service. We help users with serendipitous discovery of what to do or where to go.”

Rummble CEO Andrew Scott says the company, which predates Foursquare’s launch by more than two years, has always been about personalized recommendations for things to do or places to go. The service was built around “trust algorithms” that generate a personal profile for each user by calculating who they trust and share tastes with when it comes to places like bars or restaurants.

It later began adding features like the “check-in.” and its own variation on gaming incentives — like mayorships and badges — after Foursquare popularized them. Its version of a mayorship, called a Local Hero, isn’t about checking in the most though. It’s about being influential and reviewing the most places in a specific category or neighborhood, like bars in New York’s East Village, for example.

Now that basic location-sharing is becoming commoditized, it seems that Rummble wants to return to its original mission by leaving some of that work to other apps.

Aggregating check-ins and dealing with the overwhelming number of location services was a big topic of conversation at the South by Southwest Interactive conference in Austin over the weekend. Developers from another early player in the space, Brightkite, are gearing up to launch, a way to share your location via multiple apps from one place.

But it’s hard to say whether the companies with the largest number of active users will be so willing to share data, due to privacy concerns and because they might want to preserve their leads. Companies are only as open as it strategically benefits them. Right now, Foursquare’s application programming interface allows developers to create apps that let people check in from other places, or visualize location data. But it and other companies that have launched APIs like Gowalla have to be careful not to expose location data to an external developer without explicit user permission.