I saw this Facebook post pop up. It's quite interesting.
The guy in the story, PJ Wong, was stopped the ICA officer for a spot check. Wong questioned the intent of the officer and basically questioned all the procedures. Wong even started taking videos. The police officer tried to snatch his phone. The supervisor was called in and Wong was left off.
Here are some thoughts, the officer is doing his job and is within his power to carry out the search. The questions are unnecessary and the officer don't even need to give him any reason. The police officer has no right to take away the phone. That would be stealing. The situation can turn extremely ugly. Luckily for the officer, he did not get the phone. If I'm in the same situation, I would proceed on with the search. What's the big deal? By the way, Changi Airport is not a public area. Many people mistake places where public have access as public area. That's not true. The property owner has the right to remove you any time from the premise.
Update: There's now a facebook page to support officer Eugene Ng.