Add features to OpenGTS installation / GPS tracking

We need to customize OpenGTS installation / add some features to it. The project is near completion, but need some features like: -Ability to add Points of Interest (depending on the user logged in, only his POI-s show on the map) and show them on reports. -Ability to export to Excel -Add functionality to change map provider with the click on the button (example change from Google Maps to OpenStreetMaps) -Show visually vehicle data (location/fuel usage) on the screen based on the vehicle chosen in real-time for a chosen period of time (example, using Highcharts/Highstock or other suitable data visualization tool). -Calculate fuel usage (normalize data received from sensor, having in mind fuel fluctuation during the movement of vehicle). -Some other fine tuning as needed.