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Official Description

Oscilloscope BT allows to connect through Bluetooth with digital oscilloscope based on chip STM32F103C8T6. You can find Hardware project above this website https://myelect-projects.blogspot.com . With this app you can use the Android device just like a display to visualize the trace.
With the present edition it is possible:
Resent offset
Visualize trace
Change times base
Change volt/div
To save trace in memory
To set up trigger level
To set up the visualization single- sequence