Since its release, we have not received a single report of the Compass being confiscated by TSA or having problems passing through airport security. In fact, we travel with ours all the time and haven’t had any issues at all.
The Compass was designed specifically for travel, to be used anywhere you use your iPad including an airplane. It doesn't violate any TSA restrictions of which we're aware. However, just like your keys in your pockets or other unfamiliar metal items in your carry-on bag, you will likely need to take the Compass out of your bag and show it to them.