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

[SteveJG]

@Alzamamul_Haque

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.

Make an Analog Gauge and use it to display something useful

Make a simple Canvas based gauge and display your altitude. A simple home made gauge: uses two png images, a Canvas and an ImageSprite and a LocationSensor/GPS to provide elevation information [Altimeter2examle] The Gauge face is an image set to the background of a Canvas. An ImageSprite is the pointer. Make the pointer with a transparent background as a png image. I am not a graphic artist; use your graphic skills to provide a more elaborate image. The GPS Altitude value is used in a…

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 ( Google Search )