Hi Florian,
We're not at the point of developing specific apps like that, other than some simple example apps that do basic things like cut circles. Our focus currently is on developing the API so that app developers will be able to connect their apps to tools and send files. We should be making a doc explaining how that will work very soon but you have the right idea...that web-based apps will be one important way that apps will be developed.
In reality we're counting on others to develop the bulk of the apps so encourage you to continue working on your joinery app...judging from the response from the contest it should be very popular. If you have questions please post them and some of the guys on the software/app team will jump in and try to answer them.
Bill