• Update your devices

Most devices make Bluetooth discoverable by default, leaving your devices susceptible to unsolicited connections. Update your old devices to apply the latest security patches, which usually address known vulnerabilities. Or turn your Bluetooth off when you aren’t using it.

• Make your Bluetooth devices “undiscoverable”

To make a device undiscoverable, access the Bluetooth settings. Most devices will allow this change. Your device being undiscoverable will help keep it invisible to hackers so they can’t try to pair with it.

• Reject strange messages

Always delete messages from strangers and never click on any links within them. Sometimes these links download malware onto your device, which could help initiate data theft on an even larger scale.

• Watch out for suspicious activity

If your phone is suddenly disconnecting and reconnecting calls, or if you notice messages that haven’t been sent by you, it could indicate that someone is controlling your device. Reset the device to its factory settings or uninstall any apps you don’t recognize.

• Monitor sudden spikes in data usage

If the amount of data you use suddenly spikes beyond reason, someone could be controlling and/or using your device as part of a botnet that eats up your data.