Although not without legal dangers, bathroom spy cameras aren’t very uncommon. The biggest secret to hiding a bathroom camera effectively is to find an object that doesn’t seem out of place, although it can be somewhat difficult to find one for bathrooms.
An excellent choice for a hidden camera in bathroom is a clothes hook: you can simply put it on the door or any wall you prefer, and nobody would bother looking at it twice. Make sure to properly secure it since if someone actually does use it for hanging their clothes you definitely don’t want it to fall off and reveal what’s beneath.
Another interesting choice for bathroom spy camera is a camera in an electrical outlet or a power adapter — these might seem odd to someone who uses your bathroom every day, but occasional guests will likely keep their fingers and eyes away from it. Likely the best option is a camera behind a mirror: there’s no bathroom without a mirror in any part of the civilized world and it can be the perfect place to hide a spy cam.