@felmue Do you have an idea what the lowest (device still working) voltage is and what the maximum is? It's a 3.7V battery? But I think when it's fully charged it can be 4.2V? I've tried to find something of a table to convert voltage to % power left, but failed to find anything useful. In example code that I saw, they used something like 3.3V as lowest possible voltage, but my initial test told me that it craps out around 3.8V / 3.7V?
Or are the measurements that you get from the api just not worth while to use?