A small group of tablets now use powered styli to get around the inaccuracy problem of capacitive touch screens. Griffin’s iMarker is something completely different however, and it might have potential way beyond what Griffin intended.
The Griffin/Crayola iMarker and Colorstudio software is a j0int venture to create a coloring book/stylus combo for kids. I’ve known about it for ages (it just started shipping) but it wasn’t until I read iLounge’s review that I found out it’s powered. More specifically, it somehow manages to make the coloring app only accept iMarker input and not fingers, meaning that kids can rest their palms on the screen.
This is quite interesting because palm ignore features in various handwriting apps suck like there’s no tomorrow, and that’s a pity since having to hover your hand over the screen is tiresome and makes it harder to write accurately. So how has Griffin managed to find a way around this? Knowing what I do about various technologies, I think they’ve used a system here that’s a hell of a lot simpler than you would think. It’s only a guess of course, but I’m pretty sure that the battery is used to turn the stylus tip’s capacitive functionality on and off really fast. That way they can use the iPad’s limited touchscreen APIs to sense whether a finger is touching the screen (continuous signal) or the iMarker (pulsating signal). Again, only a guess, but it’s the only was I see this working without a ridiculously advanced system of Bluetooth connections and things I doubt you can with the iPad’s API.
Whatever it is they do, it’s likely to be easily replicated by other developers. Imagine if iMarker functionality could be built into apps like Penultimate- it would eliminate the palm issue for good. I doubt Griffin would complain either, seeing as how it would increase their sales.