I submitted my second application, DoubleTwist, to the App Store today. The last one took 9 days to approve, so I’m guessing this one will be available to buy sometime next weekend. It’s a variation on the old “pairs” game where you lay out a set of cards, turn over 2 at at time, and try to match them into pairs. But much better!

After I had decided on the name, and sprinkled it liberally throughout the application, I discovered that Double Twist is also the name of an application from DVD Jon that allows circumvention of DRM. Hopefully Apple won’t hold that against me.

Now I’ve got to crack on with the next one. At the moment it’s looking like a version of the 70’s classic, Asteroids. I’m pretty pleased with it so far though - this is less than 8 hours work, and that includes re-writing a large part, as it turns out the Quartz graphics engine is far too slow to cope with anything approaching the animation required for a real game.

I’ve spent some time trawling the interwebs

for information on how to handle collision detection. The current version uses bounding circles, which works most of the time, and I’m guessing is how they handled it in the original game, judging by the almost circular shapes of their asteroids...