>There was a chance that they would eventually find and search my laptop anyway, but I thought if I turned over my phone, they might be satisfied with that. I unlocked my phone and handed it over. The agent asked for my passcode. I selectively ignored him and chose instead to answer the other agent's questions about some items in my bag. I assume the agent with the phone decided to take it while it was still unlocked rather than wait for me to answer and risk having the phone relock and me change my mind.

Genius. 5-10 minutes after "giving in" he was on his way, laptop unsearched. This suggests a defense - have two phones...