We already knew that Google's Assistant UI would only work on the Pixel Stand. This decision by Google, while annoying, is understandable. Less understandable is the recent discovery that the Pixel 3 and 3 XL will only wirelessly charge at 10W on the Pixel Stand, with all third-party wireless chargers limited to the much slower 5W.
A reader recently purchased a 10W Anker wireless charger to wirelessly fast charge his Pixel 3 with, only to discover that the phone was only getting a maximum of 500mA via the charging app Ampere. He contacted Anker and received this response:
Also, what we learned is that Google's official wireless charger can provide 10W for the newly-released Pixel 3 and Pixel XL 3, however, according to our quality engineer, Pixel sets a limitation for a third-party charging accessories and we are afraid that even our fast wireless charger can only provide 5W for these 2x devices. Our quality team is to purchase this new models to have a try, once we get a test answer, we will keep the product page updated.
We reached out to Google PR and were told that the Pixel 3 would charge at 10W on the Pixel Stand due to a "secure handshake" being established, but that third-party chargers would indeed be limited to 5W. This is kind of a tasteless move from Google; neither Samsung (which pioneered fast wireless charging tech) nor Apple does this. So if you want fast wireless charging on your Pixel 3 or Pixel 3 XL, prepare to cough up $79 for a Pixel Stand.
Making things worse, the Pixel 3 will still say "Charging rapidly" on the always-on display even when charging at the limited 5W rate for whatever reason. Before finding out about this, I'd placed my Pixel 3 XL on both a Nimble 10W pad and a Samsung Fast Charge stand and was left confused at how slowly the phone was charging. At the very least, this behavior needs to be fixed. We've followed up with Google about this, and will update this post when we receive a response.
Google has circled back with us for some clarification. While only the Pixel Stand will charge the Pixel 3 wirelessly at full speed right now, a certification process is underway through the company's Made for Google program to allow third-party chargers to operate in the same manner, at full 10W speeds.
These certified chargers will take advantage of the protocol currently used by the Pixel Stand to similarly charge the Pixel at 10W. Belkin's got one in the works, and presumably we'll see other accessory manufacturers follow suit.
While the third-party chargers will be formally certified and able to operate with the Pixel 3 at full speed, Google's unique charging UI will remain exclusive to the Pixel Stand.