You can plug in your chosen device, phone, tablet etc. using the 3.5mm AUX/Jack cable, or you can connect directly with bluetooth.
The Bluetooth module is ON when the SOUNDBOKS is ON. This means that both AUX/Jack and Bluetooth connections can run simultaneously. One input will not block the other, however, it will play on top of each other. In the case of bystanders connecting to your Bluetooth, while being connected with the AUX simply restart the speaker.