This afternoon Thomas Degry (one of my students, www.devine.be) asked how he could program the neat little effect they use in the National Parks iPad app made for National Geographic. If you want to see the effect yourself, I suggest you download the app to check it out. Just select one of the parcs and then tap on the stats or the weather button. You’ll see a nice transition in which the master view ‘steps’ into the background, while the new content is placed in front of it.
It took me a few minutes of tapping to see how the animation works, so here is how you can mimic the effect. Just play with CALayers and some transformations 🙂