If I get food onto airplanes, I usually get cold food like fruits and sandwiches, so that it doesn't smell for other passengers. That's what I did on my first flight. But I had a tight connection and what I found between flights, in my Chicago connection, was a pizza, not too bad.
After I got in the airplane and they asked us to turn off our cell phones (after which I just put mine in airplane mode, of course), I was reading while waiting for the plane to start moving. After a while, I realized we had been parked at the gate for some time, so I put my cell phone off airplane mode so that it'd download some more emails to check in the flight, and then I started eating my Chicago pizza.
As the plane did start moving on the ground, when I was in the middle of eating my greasy and smelly pizza (which was a little embarrassing as it was), my cell phone started ringing at full volume. I couldn't quite get to it with a pizza box in front of me and my greasy hands. The guy with the pizza and the cell phone ringing when it should be off. It was a bit embarrassing.