Forgive my confusion here, I’m brand new to this and hardware in general…
But since I can power my Spark Core via USB from computer or AC, can I also power it via a portable USB battery phone charger?
Specifically: Can a USB charger like this (Amazon link below) power my Spark Core + 60-LED Neopixel strip (attached/powered via the Spark Core’s VIN pin)?
Battery life will depend on what you do with your neo-pixel strip. What you display directly changes the current consumption of each neopixel.
You can assume that unless you write your sketch to explicitly save power, the core will take about 150mA, so without any neopixels, it would last perhaps 20 hours. To last 3 hours you would want to restrict your neopixels total draw to an average of 850mA or less.
(*) All my arithmetic just takes all values at face value, the charger may be better/worse than 3Ah, and may degrade etc etc