LELink's Bluetooth OBD2 Diagnostic Tool is a Bluetooth capable OBD2 reader, that plugs into your vehicle's OBD2 port. It lets you use advanced phone-based apps to get detailed information about your EV's battery, and in some cases, change settings that normally dealers only have access to. Despite the description, this OBD2 reader works with iOS and Android devices, as long as the Android device is new enough that it is Bluetooth low energy (BLE) capable.
For the Nissan Leaf, this works wtih LeafSpy (iOS and Android) to see advanced information about your vehicle such as high voltage battery cell health, battery temperature, and more. You can also change some advanced settings such as disable back-up tones, change how doors unlock (when in Park versus when vehicle turns off, for example), and more!