There are many ways that the RPi Zero W is the same RPi Zero we've come to know and love.
For example, the Zero W uses a Broadcom BCM2835 SoC, the same used in the first-gen Raspberry Pi. (The Raspberry Pi 2 and Raspberry Pi 3 used the Broadcom BCM2836 and the Broadcom BCM2837, respectively.) The SoC runs using the same 1GHz ARM11 core and it has the same 512MB of RAM. It has the same 40-pin, unpopulated GPIO and keeps the micro USB slot for power.
The Raspberry Pi Zero W in all its glory. Image courtesy of Raspberry Pi
But the Zero W is something extraordinary even so because of one simple yet crucial addition: connectivity.
Wi-Fi and Bluetooth Capabilities
The big news, of course, is the new connectivity that the Zero W offers. The Raspberry Pi 3 uses the same radio chip as the Zero W, the Broadcom BCM43438. It supports 2.4GHz 802.11n wireless LAN, Bluetooth Low Energy, and Bluetooth 4.1 Classic.
The antenna, however, has gone from surface-mount to printed. Yep, printed right into the PCB.
The printed antenna. Image courtesy of The MagPi.
The antenna, then, is no longer an external component out to catch radio waves. Instead, the waves enter the recessed space and resonate at specific frequencies. The antenna was developed for RPi by Proant, a Swedish antenna manufacturer, who carries the InSide™ line of embedded PCB antennas. The principal hardware engineer on the Zero W, Roger Thornton, calls the Proant team "very clever boffins", which we assume is high praise in British.
The inset antenna is credited with allowing the Zero W to stay as compact as possible. The Zero W actually has the exact same dimensions as its predecessor, the RPi Zero (65mm × 30mm × 5mm). However, its new capabilities—paired with the fact that it still only has components on the top side—make it still a marvel in terms of size.
Besides, who's going to complain about the dimensions at this point, anyway? Image courtesy of Adafruit
The hardware ecosystem surrounding the Pi Zero family is in for an interesting year. RPi HATs (Hardware Attached on Top) modules and boards were first introduced in 2014 and have been booming since. HATs and pHATs designed for home automation and IoT designs have been released for years—and it seems that the ones focused on connectivity are about to meet the end of their usefulness.
The Life of Pi (Zero)
The Zero was first announced at the end of 2015. It was so cheap to produce that it was included free with the 40th issue of The MagPi and offered for $5 thereafter.
Image courtesy of The MagPi
But the fact that the Zero W is the same size as its predecessor doesn't reflect its evolution. Afterall, IoT devices have veritably boomed in the last decade, adding connectivity to refrigerators, toys, cars—apparently, anything can have Wi-Fi if you try hard enough.
The RPi family, especially the $5 Zero, has opened the door to electronics design for many. Cheap boards like these have allowed professionals to prototype ideas easily, students to learn electronics hands-on, and underserved communities to introduce engineering to their professionals and children alike.
Given the Zero W's $10 price tag, it stands to reason that it may help bring IoT designs within reach of these same disparate groups of people.
At present, the Raspberry Pi Zero W will be available in the US from Adafruit, CanaKit, and Micro Center. Check out the Raspberry Pi website for availability worldwide.