Making and android app that can communicate with arduino and act as an display for arduino

I want to make an android app that can help me use my smartphone as a display for Arduino.
The application will pair with the the arduino with Bluetooth as soon as the app will be open.
the application will have digital speedometer, odometer, digital fuel gauge, distance to empty meter etc. it will also show a small window for navigation.

Now speed sensor is connected with arduino, fuel gauge, rpm meter, everything will be connected to arduino now. right now everything can be done with an LCD but i need to make an app with proper GUI so that it can be used in any phone.

Analog Displays

Consider these two ways for using gauges with App Inventor to use analog gauges (you asked for digital indicators) but may find it useful alternative.

Digital Display

You could do something like this to mimic a LED display
A seven segment font to display numeric data - #6 by TIMAI2 Tim use a clock font, perhaps you can use a LED font ( led font - Google Search )