Stratus has built-in battery charging, monitoring, and energy-harvesting circuitry which makes it easier to connect and recharge a Li-Po battery without having to replace the battery, creating fully energy-autonomous applications. In addition, Stratus incorporates an accelerometer and a temperature and humidity sensor for detecting movements and sensing the surrounding environment, right out of the box. Finally, Stratus provides 26 mixed-signal GPIOs for interfacing with external sensors, actuators, and other electronics.