There are a lot of companies out there that let you share plans with friends — in fact, a startup called Plancast just raised funding to do just that. But Shruti Challa, chief executive and founder of a startup called Tribal Atmosphere, said none of them seem to address the needs she had as a fresh-out-of-college entrepreneur living in San Francisco.

That’s where her company’s new application, Go Tribal, comes in. The problem with a service like Plancast, or a more traditional event/invitation service like Evite, is the fact they’re built around concrete plans and events, so they’re most useful after you have some idea of what you’re doing and who’s involved. Go Tribal comes much earlier in the process, when you’re still wondering, “Hmm, I wonder if anyone wants to hang out on Friday?”

So instead of broadcasting your plans, you broadcast your availability — whether you’re “down to go out,” whether you “can be convinced,” or whether you’re definitely busy. Then someone who wants to hang out at a specific day and time can pull together their available friends to start a plan. Go Tribal also provides some lightweight tools to formalize that plan — everyone in a group can post what they’re interested in, you can do a survey, and eventually everyone can hopefully agree on a finalized plan. Instead of taking the place of something like Evite, Challa said Go Tribal really hopes to replace all the emails, text messages, and phone calls sent back-and-forth between friends as they try to coordinate a get-together.

Go Tribal has previously been limited to a private test, but is now opening up to the first 10,000 users at its website. The service is aimed specifically at young, female professionals like Challa, but she said guys are welcome too. She added that we can expect more features, as well as mobile support, to come soon, and that Go Tribal will make money mainly through offers and advertising from lcoal businesses.