Google released the March Android security update for the Nexus 6 and subsequently pulled it because it broke Android Pay, but it's all good now.
The Nexus 6 launched back in 2014 as the very first phablet in the Nexus lineup, sporting a massive 5.96-inch display. Since it's already pretty old, the smartphone reached the end of mainstream software support from Google, which means it will not be receiving updates to new versions of the Android operating system past Android 7.1.
Nexus 6 SafetyNet Fail
Nevertheless, the Nexus 6 is still eligible for monthly security updates and recently it received the latest security patch for the month of March. However, it seems that the OTA containing the March security update did some damage to SafetyNet, which in turn broke Android Pay on the device.
For those unfamiliar with the matter, SafetyNet is an application programming interface (API) that allows apps to check whether the device has been tweaked (custom ROM, unlocked bootloader and such). If the device fails the SafetyNet check, a number of apps will fail as well and that includes Android Pay, which requires a secure device to work.
In the case of the Nexus 6, the March security patch caused the device to fail the SafetyNet check even if it was not tampered with. Nexus 6 owners reported that Android Pay was no longer working because of SafetyNet even if their Nexus 6 didn't have an unlocked bootloader or other such tweaks. Simply put, their Nexus 6 smartphones previously passed the SafetyNet check, but failed it after the March security patch even if nothing else changed in the meantime.
— Kevin Burton (@MeKevinB) March 8, 2017
Nexus 6 Android Pay Working Again
Google first removed the update from the Nexus OTA and Nexus Factory Images pages to limit the impact of this issue, aiming to prevent more people from grabbing the update that broke SafetyNet and Android Pay.
On the bright side, it seems that Google has come up with a temporary workaround to make Android Pay work again. The company has re-uploaded the OTA file and the factory image in the meantime, which means the update is available again and this time, it won't break Android Pay.
By the looks of it, it seems that Google has disabled SafetyNet on the Nexus 6 for now. This means that Google is likely still investigating the issue to find the root cause, and it should re-enable SafetyNet once it figures out what went wrong. For now, it opted to temporarily turn off SafetyNet so that Nexus 6 owners could continue using Android Pay.
This could mean that even Nexus 6 owners who unlocked the bootloader or installed custom ROMs could use Android Pay, at least until Google enables SafetyNet again.
No additional information is available at this point, but more details should surface soon enough. As always, we'll keep you in the loop as soon as we learn more.