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Official Description

With Bitty Data Logger you can capture and chart accelerometer, magnetometer and temperature data from your micro:bit over Bluetooth.

After capturing data, you can upload it to the internet and then download the data to a desktop computer for analysis in, for example, a spreadsheet.

Hex files for use with this application are available, free of charge from http://www.bittysoftware.com. You'll also find a coding tutorial which will teach you how to send sensor data from your micro:bit to Bitty Data Logger running on a smartphone or tablet over Bluetooth so you can write your own micro:bit code if you prefer.