Where would you look for a bugged device?

To cut to the chase, I'm almost positive my best friend is spying on me through some eavesdropping device hidden somewhere.

What I can't figure out yet is if she somehow downloaded something on my iPhone or installed something in my room.

I've looked in most places. Obvious and unobvious.
But where and how should I keep going about this?
She blocked me on Instagram right after I started talking aloud to my family about this. She won't answer any of my texts.
How can I know if she hid anything? Or downloaded anyone on my phone?

This is serious and thanks.

Take any electronics with a camera on it to a tech support place and have them checked. Go over everything in your room again and maybe get a metal detector to see if there could be a camera anywhere (make sure anything metal or magnetic is taken out of that area first). If you really thing there's a camera in your room somewhere some places one could be is a light depending on how it stays on the ceiling, an air vent, a corner, inside something thats open. Also look for anything thats out of place from where you would normally keep it. Turn off the lights and look for a small red, green, or white light that could shine to indicate a camera or microphone being on. If she won't answer go to her house or have your parents contact her or her parents. And if you do find anything, don't move it, don't even touch it. Call the police and alert them about it.

If you are worried about your phone, do a factory reset, after backing up anything you consider important on your phone.

If she hid something in your room, it would need power, to be 0n 24/7 and then to also transmit over Wi-Fi or Cellular, even if it was voice activated. And I doubt you'd know anyone with those kinds of resources or that kind of interest in your life, EVEN if they were to plug it into your house wiring. Which of course you'd only need to check the outlets in your room/house for that.

Or if you super worried, check to see if there are any "Spy/Wireless Surveillance" shops in your town/city, and stop by and see if they have debugging services or bug finders for rent. Yeah spend money to find out if your place is bugged.

It may be possible for her to spy on you by putting some hacking type of program on your computer. If your computer has a video capability, like a web cam, then not only can you see them, but they can see you. I saw something like this on a TV crime show (cyber crimes). A bug can also be placed behind a picture, in a phone, in a vase, or anywhere else it might be easily hidden. It will usually cause static on a radio held near it. You can also talk to the FBI about this illegal wiretapping practice, and they have the instruments to detect a bug.