An add-on IPS (Indoor Positioning System) controller for an LED lighting device includes a power input port, a power output port, a housing, a control unit in the housing, and at least one data signal receiver in the control unit. A power input of the control unit is connected to the power input port. A power output of the control unit is connected to the power output port. The data signal receiver is configured to receive data from the external data source. The control unit further includes a two-way wireless module configured to send and receive the data between the IPS server and the IPS-enabled end-user device. The control unit is configured to activate and deactivate the power output port to supply output voltage responsive to the data signals.