We’ve been tracking emerging mobile-only social networks such as ZYB and Mocospace and Mig33. All have unique selling points (Mocospace is dead simple to use, ZYB has a rich set of potential users from their address book backup service, and Mig33 has a VOIP tool that has attracted over seven million users), but there’s one solid gold feature that none yet have: physical presence detection and information exchange with other users.

This is the Holy Grail of mobile social networking, and one of the main reasons for taking the networks off the desktop/laptop environment in the first place. Imagine walking into a meeting, classroom, party, bar, subway station, airplane, etc. and seeing profile information about other people in the area, depending on privacy settings. Picture, name, dating status, resume information, etc. The information that is available would be relevant to the setting – quick LinkedIn type information for a business meeting v. Facebook dating status for a bar.

Knowing when your friends are around, and having the ability to meet new people who share your interests (even if it’s just that you are both single), will drive massive usage of networks. But, as with many new services, a chicken and egg problem looms. Until everyone is using this, there is no real reason for anyone to use it. Meetro, an instant messaging service that finds friends based on location, has struggled to gain users over the last couple of years for this reason.

Technical barriers aren’t an issue – cell phone tower triangulation and bluetooth solve a lot of the problems of locating users and transmitting information between phones. What’s harder is just plain getting a critical mass of users.

The Failures

There is a trail of failed attempts at getting this right. Nokia released Nokia Sensor nearly three years ago. It broadcasts information about yourself to others via bluetooth. Never heard of it? Neither has anyone else, although it is still available for download. Google’s Dodgeball is another example that’s fallen flat – it tells friends (and friends of friends) who are within 10 blocks of you where you are and what you are doing.

The New Experiments

A bunch of new startups are giving this a shot, too. In a post yesterday TechCrunch UK mentions Germany’s Aka-Aki, Paris-based Mobiluck and MeetMoi (the lone U.S. startup). Another startup is Copenhagen-based Imity. It’s not surprising that most of the innovation is occurring in Europe. The current approach is to get java-based software on the phone – very few U.S. carriers and handsets allow user-based installs of java apps.

Aka-Aki

Aka-Aki, based in Germany, is just a couple of weeks old. Create a profile and download the java app to your phone. You can also create and join groups that say things about your life, job, etc. When you are near other people who are members, data about you is transmitted to them via bluetooth, and vice versa. Users have control over data flow with privacy settings. And the groups supply another layer of privacy. You may transmit that you are single only to other singles, for example. Or share your sexual orientation only with others with the same orientation.

After a silent launch, word is getting out. Thousands of people in Berlin are using the software, and there is a chance for them to get critical mass there with proper marketing. The company has raised a small seed round from FoundersLink and is currently looking for a larger round.

Imity

Copenhagen based Imity, which launched in April, has also been flying under the radar. Like Aka-Aki it detects other members via bluetooth and send basic profile information to your phone. It also keeps track of people on its website, so you can check that out periodically from your normal computer. It’s bridges mobile and traditional social networks, which may help it gain critical mass. Co-founder Nikolaj Nyholm is also behind Polar Rose, a facial recognition and image tagging service.

Imity went open source in February 2007.

MeetMoi

MeetMoi, the only U.S. based service, is most like Dodgeball – it uses text messaging to help connect people. It’s dating focused – text your location to the service and it notifies other users in your area that you are there. If they are interested, they can contact you. The company has raised $1.5 million from Acadia Woods Partners and is based in New York.

MobiLuck

MobiLuck, based in Paris, is another bluetooth solution similar to Aka-Aki and Imity. Download the software to your phone and it vibrates when other users are nearby. You can then chat with them, send photos, etc.

Update: Per a comment below, we’re adding Britekite to the list. We actually covered them briefly last month as part of the TechStars event.

Y Combinator wasn’t the only incubator to demo their most recent startups today. Colorado-based TechStars also brought their startups on stage – ten of them – to give the audience a first look at what they’ve been up to all summer. Each startup gave 5% of their equity in exchange for $15,000, operational support, office space and mentoring.

Most of these companies are unlaunched and seeking additional angel funding (exceptions are noted). Here are our notes on each – and see Don Dodge for his take:

EventVue builds social networks around conferences (see confabb, an existing competitor). The idea is to let people connect before, during and after conferences in an online space, to add to the physical interaction at the conference itself. The company plans on generating revenue by charging an affiliate fee for each new registration. They are currently looking for $150k in funding.

Intense Debate – see our previous coverage. Intense Debate is a souped-up blog commenting widget that adds a lot of features for publishers and commenters alike. Currently installed on 30 blogs. Installing the plug-in on your blog (WordPress, Blogger, and TypePad) adds threading, comment analytics, bulk comment moderation across all your blogs, user reputation, and comment aggregation. They are looking for $500k in funding.

socialthing! is an ambitious project that simplifies the management of digital content (blogs, photos, music, friends, social networks and links). Users can also synchronize information from and to various social networks from their profile page. Strong viral component. Revenue from advertising. Raising $500k.

J-Squared Media has launched their “Sticky Notes” Facebook application. It has 1.7 million users after six weeks, who have sent over 4 million sticky notes. They are working on several other related Facebook applications and are cash flow positive with $30,000/month in revenue from cost per action advertising. Not seeking funding. More here.

Search-To-Phone is a mobile search service via voice. Call and leave a voicemail asking about a product or service. The request is then routed to the appropriate business to call you back with information and/or a special offer. Built on TellMe and Gold Systems technologies for voice recognition. They’ve signed a business development deal with Excell Services to provess 10 million calls. They are looking for a small capital investment and more partners before launching.

Villij is a recommendation engine that analyzes your online life (social networks, blogs, bookmarks, etc.) to find people who may have similar interests as you. Raising $500k.

MadKast has the honor of being the first TechStars startup to launch. Our previous coverage is here. They’ve made a dead simple way to increase distribution for your blog with one line of javascript or one click for Blogger and TypePad. Once the widget is installed, readers can send a blog post via email, mobile MMS, or social bookmarking networks to friends. They are raising $300k in capital.

FiltrBox is a content monitoring and filtering service for blogs, news sites and other websites. Content is filtered by topics, keywords and context and then delivered to the user via RSS, email and/or text messages. Filters can be adjusted via sliders and will learn what you like over time. Raising $500k in capital.

KBLabs is developing Facebook applications and widgets. Wah! Cool was their first application, which launched four weeks ago. It now has 100k subscribers and is generating 1.5 million page views per week. Other applications include Post Secrets, Motivate Me and Track Bot. The founders are going back to college this Fall but will continue to consult and build Facebook applications. They are not looking for funding.

BrightKite serves location based notifications (”place streaming”) over email, instant messaging of text messages. The idea is to stream content about a place, from a place. Friends are alerted when you are nearby. You receive offers from local businesses. Etc. Targeted towards conferences, bars, parties and public places. It is also a platform for third party applications. Raising $500k in capital.

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