I've heard of pocket dialing, but today I somehow managed to "pocket purchase" an Audible book! I pulled my phone out of my pocket, and found it awake and open to the Kindle app with a message that said something like: "thank you for purchasing the Audible version of Armada". A minute later I got a notification from my credit card company about the purchase. Experimenting with the Kindle app, it wasn't too hard to see how a few random touches near the top of the screen could order the Audible version of a book in my library (for books that have Audible support, there's a big orange button in the book settings screen that says "Add Audible Narration [Buy for $10.99]", what I couldn't figure out was why my phone was unlocked while in my pocket. I use a pattern lock, and have "Lock instantly with power key" turned on, and my habit is to turn the screen off with that button before sticking it in my pocket. I never stick the phone in my pocket with the screen still on, and once it's locked, random presses of the home or power button while in my pocket may wake the phone, but not unlock it, so there's no way this should happened, right? After a lot of head scratching and fiddling around, I finally figure it out. There is another setting in Lock Screen settings called "Lock automatically" which determines what happens when the screen turns off due to timeout (as opposed to using the power key to lock it). In my case, I had this setting configured to wait 15 seconds before locking the screen after a timeout. At the time the book got ordered, I had just arrived at the store, pulled my phone out of the holder in my truck and put it in my pocket, apparently within that 15 second window after the screen had timed out, so the screen was off, but not locked. A few seconds of bouncing around in my pocket, and... book ordered! Needless to say, I changed the "Lock automatically" setting from "15 seconds" to "Immediately".