iPhone keeps connecting to mystery Bluetooth devices

It is going to take a screenshot of what you see when those devices appear in your Settings. Without an info button next to a Connected device, it means that an app you have installed was used to connect the device. You can review apps that are allowed to access Bluetooth connections by going to Settings > Privacy & Security > Bluetooth, and can revoke Bluetooth Access. Management of devices that are allowed to connect through an app are done within that app if you want to continue to allow Bluetooth access.

Disable that one popular music app that is enabled in Bluetooth, and if the device you see here immediately goes away, you have found the app.

You will need to revoke all apps that have been granted Bluetooth access, not just certain ones. It is easy to identify the app, as the device will be removed from bluetooth when access to the app has been revoked. I have not had to restart my device after revoking myself, but you may want to try that.

And to confirm, we are only talking about the one that does not have the info button next to it. That is one that is allowed by an App where you have allowed it to access Bluetooth. Post a screenshot of what you have at Settings > Privacy & Security > Bluetooth.

iPhones do not in anyway shape or for connect automatically to other bluetooth devices. Much less android devices. iPhone's do not support direct Bluetooth connections to other iPhones, iPads,. android phones, PCs or Macs at all. So will not connect even when you directly try to.

Connecting to devices requires deliberate action in your part to select and pair them and enter a pairing code for most things that can be connected, such as headphones, speakers, keyboards, mice and yes car stereos.

When you open bluetooth settings, the iPhone will scan for any devices around and will list them under "other devices" since it assumes you want to connect to one as that is the primary purpose of the bluetooth screen in Settings.

Connected devices including your car will appear under the "My Devices" section and show the word "Connected" if they are currently and actively connected.

With that said, it's entirely possible there may be some interference between your iPhone and the vehicle's audio system while you drive or that the vehicle's audio system is having some issue too.

It's unlikely any devices are directly connecting to the iPhone, but multiple Bluetooth signals nearby can cause interference.

If there is no i on the Bluetooth Device, this indicates in this case this Bluetooth accessory has been paired via an app of yours which only communicates with that one app. They must be explicitly setup and within a few feet to operate. So figure out which app that is, you can go to Settings > Privacy and Security > Bluetooth > Disable access to apps and see if it goes away, especially any Google apps.

If you have the Google Home app installed, that would be the first one to revoke. Anyway review the list you have at Settings > Privacy & Security > Bluetooth.

Apps can read input from devices through a BLE Bluetooth connection which is what this is. This would be possible with a Music player app where another device can change the music selection in the app. It is also used commonly by Google Home, which is why that one was suggested as a possibility. It is not a traditional bluetooth connection where you are required to pair the device in the Bluetooth Settings, and the devices are managed by the app when Bluetooth access is allowed for the app.

Are you sure that you are connected to these devices, or is it they are just appearing in your Bluetooth list. Do they actually say Connected? I don't think they do, as if they were, you would see the (i) to tap on.

I know I responded earlier, but after looking at this image, I Googled that NUU A25im and that is an Android phone! Not sure how that is connected.

Thank you. I understood what you were saying earlier, and I just wondered if that was one of the connections the OP was concerned about. It did not appear in earlier images, but was in this last one.