iPad apps for physics teaching

At the AP reading, and again at my summer institutes, physics teachers showed me all sorts of applications for their handheld devices.  As I expressed reluctance to dive into such trendy tech gear, Karie Meyers (a college professor at my table) sat me down and told me bluntly -- mobile apps are here to stay.  Teenagers use them fluently.  Either learn to use them, Greg, or be considered a dinosaur by your students. 

Based on her prodding, and further kicked in the butt by the attendees at Kennesaw State, I asked Woodberry's tech director about iPad apps.  He had bought one iPad to share around departments, to see whether anyone could find a serious academic use for it.  I am his first guinea pig - I have been using the iPad over the weekend.  I've found apps to measure magnetic field (free), to find current and predicted weather and barometric pressure (free), to measure the angle of the iPad (free), and to show and name stars in any direction (not free, but bloody impressive). 

I want to find something to make position- and velocity-time graphs using the internal accelerometer.  Pasco makes a free app that will plot acceleration vs. time, but I can't figure out how to derive the other plots on the iPad.  (Pasco also claims that this app can plot output from ANY of its probes using bluetooth.  Great, but I have Vernier, not Pasco, probes.)

I've found other cool apps that are only tangentially related to physics teaching, like google earth, a giant timer, a ruler, a periodic table, and so on.  There are physlet-style simulation apps available, but (a) they cost money, (b) they're available online for free, and (c) I'm not a huge fan of simulations for teaching purposes, anyway.

I have little doubt that, five years down the line, Pasco and/or Vernier will have updated their data collection line such that the probes work wirelessly with the iPad or equivalent, and the LabPro or LabQuest will be unnecessary.  That's why I need to start figuring out how to use these things now.

What I want to know from your comments and emails:  What data-collection apps are available?  What apps might I use directly or indirectly in my classroom?  Give me some ideas to track down...

GCJ