The VE.Bus Smart dongle is two products in one:

First of all it is the bluetooth accessory for our range of inverter/chargers: Multis MultiPlusses MultiPlus-II MultiGrid MultiGrid-II Quattros and our series of Phoenix Inverters with a VE.Bus port. When installed use the VictronConnect app to monitor operation and also operate the system: change the input current limit as well as switch between Off On and Charger-only modes.

Secondly it can work as a Voltage- and Temperature-sense device for the inverter/charger. This works with all models and is especially useful in combination with the MultiPlus-II as it does not have on-board terminals for Voltage- and Temperature sense wiring

For monitoring the device is a great alternative in caravans smaller yachts and motor homes for which the Color Control GX or Venus GX are a step too far.