No, you can only pair one Everion Device via Bluetooth Low Energy (BLE peripheral) with one mobile device (BLE central) at the same time. Sequentially you can pair as many as you need. The Everion Device has a unique ID which is advertised via BLE.
If you want to connect another mobile device (another iPhone, iPad or iPod etc.) with your Everion you have to unpair your Everion from your currently paired mobile device. To unpair your device go to setting und click "Unpair Device".