This G-Force Meter app measure resultant force and speed.
It shows you velocity, speed, acceleration, and deceleration forces.
This app has a digital Speedgauge which uses GPS system and a f1 formula style G-Force meter.
So you will need an active GPS connection for the app work.
Kilometers(km/h), miles(mph) and Nautical mile(kts,knots,kn) are supported in this app.
You can use this app with bike smartphone holder, winding road car, skidpad(skidpan) car's handling test and anything else.

How to use.
When you use this g-force meter,
You must fix your device tight, after fixing the device push the "Calib" button.

NOTE.
Due to phone GPS limitation, It may not work well in cloudy weather or indoor places.
And I don't guarantee that it shows accurate data because of GPS errors.
Some phones will give different sensor readings based on the hardware used by the manufacturer.
And Some phone having a bad sensor(or error sensor) will show inaccurate result.