ARDUINO MKR ZERO gives you the power of an Arduino Zero in the smaller MKR format. The MKR ZERO board serves as a great educational tool for learning 32-bit application development. It has an on-board SD connector with dedicated SPI interfaces (SPI1) that allows you to play with MUSIC files without additional hardware! The board is powered by Atmel's SAMD21 MCU, which features a 32-bit ARM Cortex® M0+ core.
Warning: unlike most Arduino and Genuino boards, MKR Zero operates at 3.3 V. The maximum voltage that the I/O pins can tolerate is 3.3 V. Applying voltages higher than 3.3 V to any I/O pin could damage the board. The board contains everything needed to support the microcontroller; simply connect it to a computer with a micro-USB cable or power it from a Li-Po battery. The battery voltage can also be monitored since there is a connection between the battery and the board's analog converter.