Last year, Google made big news by announcing that its upcoming version of Android, Lollipop, would use full-disk encryption on all new phones. Old Android phones already had the option for full-disk encryption but Android 5.0 Lollipop would make it a default feature.
Both the Nexus 6 and Nexus 9 phones were encrypted by default. However, 3 months since Lollipop‘s release, new phones from third parties and even the Galaxy S6 aren’t encrypted by default. Old phones that were upgraded to Lollipop also didn’t get the default encryption but that is understandable since phones not built for encryption might have some issues.
9.9 Full-Disk Encryption:If the device implementation has a lock screen, the device MUST support full-disk encryption of the application private data (/data partition) as well as the SD card partition if it is a permanent, non-removable part of the device. For devices supporting full-disk encryption, the full-disk encryption SHOULD be enabled all the time after the user has completed the out-of-box experience. While this requirement is stated as SHOULD for this version of the Android platform, it is very strongly RECOMMENDED as we expect this to change to MUST in the future versions of Android.
In other words, it is still up to the original equipment manufacturers (OEMs) to decide whether they would like to turn the default encryption on or not. According to Ars Technica, this change might be to prepare OEMs for the hardware transitions that are required for this feature. Google hasn’t, as of the time of writing, said anything about it.
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