The easiest way to avoid suspicion is to have a phone filled with cat and family pictures, dumb apps and games.

You don't avoid scrutiny by being wierd and hiding things, but by hiding in plain sight by being ultra boring.

On the other hand, if everything about you is boring, that in itself may begin to seem suspicious. "I borrowed this old phone from my stepson because my own phone got run over by a steamroller at a vintage vehicle show" is the sort of thing an actual spy or criminal would never say.