How do you tell if a camera is watching you?

7 Simple Ways to Detect Hidden/Spy Cameras

Check for any unusual objects in the room.
Turn off the lights and use a flashlight to spot hidden cameras.
Look at the Wi-Fi Network.
Use mobile phones to locate hidden cameras.
Use a professional camera detector or sensor.
Check if there's a hidden camera behind the mirrors.

Can I tell if my phone is being monitored?

However, if someone is spying on your phone, there are common signs you can look out for. You may notice a rapid increase in your phone's data usage, suspicious files or applications, or strange text messages that you don't remember sending. Your device may also show signs of malfunctioning behavior.