GBZ Power Supply

Adafruit Powerboost 1000C

Adafruit Powerboost 1000C

Pros: Well documented with Wermy's guide Very simple & easy to use, multiple power outputs Has integrated Low Battery Warning LED & pinout for custom circuits to catch this. Integrated Power, Charging, & Charged LEDs. Integrated on/off function by shorting EN pin to GND. Cons: Most expensive model by far Availability is often questionable, especially after a news article or custom board release increases demand.

Alternatives

Adafruit Powerboost 500C

Adafruit Powerboost 500C

Pros: Slightly Cheaper than the 1000C Usually easier to get than the 1000c Check Cons below, is otherwise identical to the 1000C. Cons: Can only charge at 500mA (half the 1000C's rate) Does not have the same "Load Sharing Circuit" claimed by the 1000C Is not suitable for charge & play

Banggood Model

3.7V Li-ion Battery Mini USB To USB A Power Supply Module

Module is able to power a device and charge the battery at the same time. Pros: Fraction of the cost of the Adafruit models. Almost always available. Cons: Excessive shipping times (20-30 days to USA). Not as well documented as the Adafruit Models No Low Battery function on-board, outside monitoring is required. Has LED lights to indicate the state: Red led: charging Green led: finished charging Blue led: board is powering a device