There are two giant upgrades in the Pi 3. The first is a next generation Quad Core Broadcom BCM2837 64-bit ARMv8 processor, making the processor speed increase from 900 MHz on the Pi 2 to up to 1.2GHz on the Pi 3. The second giant upgrade (and this is the one we’re personally most excited about) is the addition of a BCM43143 WiFi chip BUILT-IN to your Raspberry Pi. No more pesky WiFi adapters - this Pi is WiFi ready. There’s also Bluetooth Low Energy (BLE) on board making the Pi an excellent IoT solution (BLE support is still in the works, software-wise) Lastly, there’s an upgraded switched power source that goes up to 2.5 Amps instead of just 2 Amps - allowing your Pi to power even more powerful devices over USB ports. The best part about all this is that the Pi 3 keeps the same shape, connectors, and mounting holes as the Pi 2. The only difference is a slight change in where the LEDs are. 99% of cases and accessories will still be fully compatible with the Pi 3, Pi 2, and Pi B + - though if you have a case with a metal top there might be some WiFi chip difficulties. A 1.2GHz 64-bit quad-core ARMv8 CPU 802.11n Wireless LAN Bluetooth 4.0 Bluetooth Low Energy (BLE) Like the Pi 2, it also has: 4 USB ports 40 GPIO pins Full HDMI port Ethernet port Combined 3.5mm audio jack and composite video Camera interface (CSI) Display interface (DSI) Micro SD card slot (now push-pull rather than push-push) VideoCore IV 3D graphics core The Raspberry Pi 3 has an identical form factor to the previous Pi 2 (and Pi 1 Model B+) and has complete compatibility with Raspberry Pi 1 and 2.