Just as the World Wide Web has Web 2.0 - which has brought us blogs, MySpace, YouTube, etc - VoIP is promising to bring us 'Voice 2.0' (as Iotum co-founder and CEO Alec Saunders called it in last year's Voice 2.0 Manifesto).
Simply put, Voice 2.0 is the promise of voice being just another network app made good. It's not just about carriers adopting VoIP services but integrating voice into the Web to the point where the value isn't in the meter, but in the voice app itself, thanks to protocols like VoiceXML, SIP and SALT, as well as elements like presence and directories. Think of Skype being incorporated into eBay, and you'll get an idea of where this is going.
One thing that's been missing from all this is the mobile equation. Inevitably VoIP will run over mobile phones one day, but it's going to take post-HSDPA/EV-DO Rev A speeds to make that viable. Or really good dual-mode cellular/Wi-Fi networks.
As it happens, a Stockholm-based company named RebTel is hoping to pull that off a little sooner. Like, now.
The RebTel VoIP model - as described by co-founder and CEO Greg Spector during a presentation I witnessed last month at a Globalpress IT Summit in California - doesn't rely on client software as Skype does (a factor that has limited Skype's mobility to PDAs or smartphones with Wi-Fi connectivity). Instead, RebTel cleverly leverages on the trend of bucket voice minute plans being offered by cellcos around the globe by turning IDD voice into a local call. This is done by borrowing a page from that other great IDD arbitrage tool, callback. When you call someone overseas (who is also registered with RebTel), their phone rings, and they immediately hang up and call you back. The trick is that your end of the call is still connected, because it's a local call. Meanwhile, your friend has just made a local call to your number. RebTel connects the two local calls over the Internet, and you can talk normally - and both parties are only billed for the local minutes from their voice-minute plans (plus one dollar a week from the RebTel subscriber).
No wonder Jeff Pulver is totally in love with RebTel, which he's described on his blog as 'one of the most exciting startups that I have met in 2006' and one that could potentially be 'bigger than Skype'. He's got a point. The RebTel model is interesting because it reaches way beyond the high-end smartphone segment into the mass market. And unlike Skype, it's SIP-based.
Still, there's plenty to be skeptical about. Some have expressed concerns over the legality of the service, but Spector insists it's 100% legal and breaks no rules (at least not in the 38 countries RebTel serves, where VoIP itself is legal regardless of whether it originates from a PC or a phone). And he's probably right. Personally, I see two bigger potential roadblocks.
One is that RebTel doesn't roam. Your RebTel number only works in your home service area. When you go overseas, you'll still be paying exorbitant roaming fees as well as IDD calls. Granted, the vast majority of mobile users spend more time at home than they do overseas, but mobile users spend far more time complaining about the cost of roaming than they do over the cost of IDD.