Multi touch applications, where to start

Last week at CodeCamp 2009 Buenos Aires, a question arose when talking about Microsoft Surface apps: how do we create Touch-enabled applications? The answer is not straight forward as it seems.

If you actually want to create develop surface computing applications (multiuser, object recognition, 360 degrees UI, multitouch, direct interaction), you should stick to Microsoft Surface. With its SDK, technically speaking the Microsoft Surface SDK 1.0 SP1, you will get all the tools you need to develop, including API reference, cool controls (many demo applications just use the built-in controls), code samples and a complete documentation. You can download the SDK from a MSDN subscription of Registered Partner level or above.

But if, in fact, you want to create multi touch applications for multi touch desktop PCs, you can do that using Windows 7 and WPF. While in WPF 4.0 (not yet released, just beta) the multi touch capability will be part of the API (including gestures and manipulations), right now with WPF 3.5 the multi touch is achieved using custom frameworks or interop libraries, like this. Is important to remark that this library supports gestures like pan, zoom, rotate, the ones we are used with Microsoft Surface, but no the controls (ScatterView for instance; this one is available in WPF 4.0, source here). Also here you can get design guidelines for touch solutions. The good thing is you don’t need to have a MSDN subscription to start coding, and also, a desktop is far cheaper than a Surface Unit obviously.