Around two months ago some guys from The Media Computing Group at RWTH Aachen University started working on an interesting framework to develop multi-touch applications with Mac OS X. The idea is to develop applications which input could be easily switched between iPhone (or iPod-Touch), camera (FTIR / DI) or a TUIO server application.
The main problem is probably the fact that often the final set for a multi-touch installation is not very portable or replicable (ie. Microsof Surface, which is big, expensive and very rare). So you can imagine how problematic it could be when the development team is composed by more than a person. MultiTouch Framework tries to address it and I have been lucky enough to be accepted in the beta program. Lucky because Apple refused to add the application, which allows to use as input the iPhone, on the AppStore, but the guys were so kind enough to add the allowed developers in the provisioning file. So yesterday I received the required files and today in no time I was already testing the framework!
A gem from the release notes I would like to mention is: "We donʻt have a NDA, so you may talk and write about the framework if you like". It might be because the legal implications of having an NDA, but I like to think that they are pro openness, at the contrary of Apple.
The only input which can be used at the moment is the iPhone which communicates through the network to the Mac. They recommended to use the Mac as wireless spot and connect the device straight to it, but in my small wireless network at home it works pretty well also without this trick, and I reckon this might be enough for most of the tests.
The main problem of using an iPhone to test multi-touch applications is firstly the size. We know that in general these kind of applications are multi-user and are showed in big surfaces. As you can imagine the surface of the iphone is pretty small, and it could be quite hard to test an application on a 1:10, or even smaller, screen. Other issue is that iPhone handles maximum 5 fingers. It's true that they might be enough for most of the needs, but it can still be a limitation.
My next step will be to write a mac app which can communicate to Flash via binary socket so that I can use the iPhone as multi-touch input for flash applications, using the same technique I used here.