How to measure the height of a building with a smartphone? Here are two concrete examples, step by step.
method number 24: trigonometry
method number 15: giant pendulum and light sensor
Phyphox is an open source and free application developed by the university of Aachen, and is available in various languages. More info on phyphox.org.
Fizziq is another application that can access smartphone’s sensors. It was developped in collaboration with the Main à la pate foundation, is free and require no registration. More info on fizziq.org.