TerraNet breaks the numeracy barrier

The perceived wisdom is that you can't sell a mobile phone to those with no numeracy sales. Yet Sweden's TerraNet has just devised a handset interface where numeracy isn't a requirement.

The UI is simplicity itself, requiring only three buttons to govern the complete control of the handset. However, it's the way that the handset dispenses with the need for a traditonal addressbook – not just dialling by using numbers – that's the most fascinating part.
According to TerraNet's CEO, Anders Carlius, the solution is to take photos of everyone you wish to call. These photos can then be transferred to the handset via an infrared connexion.
This whole UI concept was invented because TerraNet intends to sell its phones to third world countires. Carlius argues that people in some third world societies don't even have recognisable names, so they use facial recognition instead.
TerraNet has reasoned that not only do some societies lack numeracy but they will also illerate, too. So that would seem to remove the need for adding an SMS capability to such handsets.
The company may be missing an opportunity. I'd suggest that it would be possible to link texting to specific ringtones – or, in this case, 'texttones'. Each texttone would have a specific meaning.
The sender could scroll through the textones until he or she hears the one required. The intended recipient could be selected from the photos. The handset would send a specific instruction via SMS and the receiving handset would play the selected texttone.
The three button interface hasn't actually been built into any products at this moment but TerraNet might have solved a UI problem that until now has defeated vendors of traditional mobile phones.