You've probably heard a lot about Google Voice since Apple punted it from the iTunes App Store: It's a free telephony service that allows one phone number to ring all your phones. It also lets you receive and send SMS messages on your computer, centralize your voice mailbox on the Web, block and re-route callers, record calls, and perform other bits of phone-related chicanery. The only real problem with Voice is that it's hard to get into--you need an invitation. And like all things Google, it's still in Beta.
But now a competitor is making the rounds with a product that does many of the same things as Google Voice. It's called 3jam, and it's from a venture-backed startup that focuses on Internet-enabled SMS messaging (which it calls SuperText). It also does all the obligatory phone stuff that Google Voice does.
3jam has a few salient advantages. First, and most important, you can sign up now (no invitation required). Plus, it's text messaging is better than Google Voice's: If you're logged into 3jam on your computer, your SMS messages (and MMS, too) go to your PC, not your phone. Google Voice can't do any kind of MMS, and it's not as robust with how it handles messages. You can also reply-all and do other email-ish stuff, as well as transcribe voicemails and interact with VOIP services including Skype.
If you're not at a computer, messaging gets a little wonky. To add people to your address book, you need to send text commands to 3jam's system so that it knows how to route your message. (Once someone's in the system, it's easy, but that's still a barrier to entry.) After that, you just send 3Jam's special number a text telling it which person or group to message: "text volleyball, game tonight?" is the example they give. Who plays organized volleyball? But I digress.
In a sense, 3jam is a little like the Posterous of Internet-enabled phone systems. It uses a tool you already understand (as with Posterous and email) and lets you send all your commands through it. Whether you're a Tumblr or Posterous kinda person depends on your personal taste; some people like proprietary tools like Google Voice's mobile site or Tumblr's Web dashboard, while others like the lite-and-thin approach.
3jam can assign you a number based on any geographical location in the U.S., which is one of the popular features of Google Voice, and it also does a good job integrating international calling and texting for a low price. And it beats Google in one respect: While Google has said that number porting will be available soon, 3jam already has number porting up and running. That means that you can switch to a 3jam lifestyle without giving out a new number--something that is a huge stumbling block to converting to life with Google Voice.
One final advantage to 3jam--at least for the techies among you--is its open API. You can futz with Google Voice too, but that API is undocumented and relatively limited.
Here's the thing that sucks about 3jam: You have to pay for it. Not only that, it's nearly impossible to figure out just how much you'll end up paying for it. The site says you get your first 40 domestic texts for free, and because many are delivered to your PC while you're logged in, that should cut down on traffic too. But after that, it's several cents per text, plus a monthly fee for voice minutes. Google Voice is utterly free unless you're doing international calling. 3jam packages start at $5 a month.
If 3jam can simplify its pricing, it could become an uninvited competitor to Google Voice.