I ended up on the Truphone web site today after a bit of browsing. I do like their approach and positioning, I reckon they've got it bang-on for their target market.
Another shrewd partof their approach has been to concentrate on one mobile phone platform, Nokia. So many mobile application vendors try and work across multiple devices and end up underwhelming everyone. I've no doubt they have plans for other platforms, almost certainly Sony Ericsson after their stellar rise to prominence in the last year or so, but they've given themselves the best chance of success by carefully choosing the battleground.
While there, I discovered their How Truphone Works page. They eulogise about the wonders of using open source software components plugged together to make their service work.
We do make use of open source software at Esendex but more in a supporting role than in our core system. This isn't through any fundamental opposition to using open source software, more a indication of the maturity of the open source industry in our chosen development environment.
Our systems are 100% Microsoft.Net, coded in C#, hosted on Windows servers. The open source systems with the most active development and mature feature sets are predominantly designed for Linux systems, coded in C.
So we've had to develop everything ourselves. Good news is that the system works just the way we want it to without any unnecessary functionality. Bad news is that it's taken us a longer to get there.
We have found a place for open source software, we use NUnit for unit testing; NAnt for build automation; Log4Net for application logging; Ethereal for network communication diagnosis; along with a variety of supporting libraries in our SMS SDKs for the open source environments.
The open source movement has been phenomenally successful and has provided a fast track for many companies. For us it's helped us make better systems.