I'm not 100% sure I understand the question?
For single reads, analogRead is easiest. For multiple reads you could use Waveform and I think that should be slightly faster.
You can also configure the nRF52 hardware to just take readings automatically which is probably the fastest - see https://www.espruino.com/NRF52LL#read-a-buffer-of-data-from-the-adc
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
I'm not 100% sure I understand the question?
For single reads, analogRead is easiest. For multiple reads you could use Waveform and I think that should be slightly faster.
You can also configure the nRF52 hardware to just take readings automatically which is probably the fastest - see https://www.espruino.com/NRF52LL#read-a-buffer-of-data-from-the-adc