“Resume on Reboot” will make OTA updates even more seamless on the Pixel 4
...and some other phones
Whenever you install an update on your phone, you have to unlock your device when it reboots in order to make sure all the apps start working properly. This could be especially annoying to deal with in case you have enabled automatic update and an update installs overnight. In such a case, many apps won’t start until you unlock your phone the next morning, which might result in you missing important notifications. In order to address this issue, Google is now working on a new feature called “Resume on Reboot”.
For those of you who are unaware, there are two ways in which OTA updates are installed on your device. In the case of devices that don’t have an A/B dual partition, the OTA update package is downloaded to the device’s cache, the device then reboots into recovery and the OTA update package is flashed through the recovery. On the other hand, in case of devices that have an A/B dual partition, the OTA package is downloaded to the device cache, flashed to the inactive partition, and then the newly updated inactive partition is swapped with the other partition when the user reboots. The latter of the two methods offers a more seamless experience as the user doesn’t have to sit and wait in the recovery for the update to flash. In either case, however, the system still requires you to unlock your device after it reboots in order to complete the installation. And this is where “Resume on Reboot” comes into play.
With the new “Resume on Reboot” feature in place, you won’t have to enter your login credentials after a successful OTA update. The feature was recently spotted on the Android Gerrit and according to the description of the AOSP commit, the recovery system will be able to securely store the user’s lock screen knowledge factor when an OTA is downloaded. However, since the feature requires a HAL called IRebootEscrow, it won’t be coming to every device. But we expect to see it on flagship devices as most of these devices fulfill its secure hardware requirements. The commit for the “Resume on Reboot” feature has already been merged and Google is currently testing it on the Pixel 4. The feature will most likely work on the device following a future Android 10 update or in Android 11.
Thanks to XDA Recognized Developer luca020400 for the tip!