The Wall Street Journal reports that T-Mobile will extend its converged cellular/Wi-Fi calling plan and hardware nationally: The plan, called HotSpot@Home, has been available in Washington State since October. The Journal calls that "Seattle" and "a few months," a dramatic understatement of how long T-Mobile has taken to shake the bugs out of this service. I was starting to wonder whether T-Mobile would ever launch nationally. The launch could happen in mid-June.
The converged plan uses a handset with both GSM and Wi-Fi radios built in, allowing seamless roaming among preferred personal hotspots (home, for instance), the T-Mobile HotSpot network in the US, and the GSM network.
When I tried it and wrote it up for The New York Times last fall, the roaming part of the operation--from cell to Wi-Fi and Wi-Fi to cell--wasn't up to snuff, but I like the Nokia phone I tried and Wi-Fi-based calls sounded great. The Journal says those problems have been ironed out through handset improvements, which I believe. The technology would seem to me to involve a lot of tweaking, rather than overcoming insurmountable odds.
The article notes that the $20 additional monthly fee for unlimited Wi-Fi calling, and $5 per month for subsequent phones in family plans, could be tweaked for the national rollout. In the Washington trial, you can also pay nothing and use normal minute plans to make Wi-Fi calls if you're after improved call quality in your home instead of more minutes.
An intriguing option I hadn't heard would be to extend the plan, allowing a landline connection in the home to use the same system, although it hasn't been set for launch. This is extremely simple to do because it involves no roaming and probably very little hardware--an additional plug on the routers that T-Mobile offers to customers with this plan. The router is free ($50 minus a $50 rebate), and supports WMM Power Save for improved battery life and WMM for voice prioritization over the Wi-Fi network.
The reporter hasn't done his homework, because he says that three European carriers are "launching" Wi-Fi phones: BT launched back in January, and seen 40,000 subscribers by early April, according to Light Reading. BT's plan includes their OpenZone hotspots, home service, and GSM as well. France Telecom's Unik converged service has done far better, with 100,000 subscribers, due in part to the telecom's success with a bundled broadband offering that has put 3.5m gateways into homes. These gateways are optimized for calling over Wi-Fi; BT and T-Mobile need to get gateways into homes, which is a higher bar to gain customers.