Stock Android HTC One (M8) Google Play edition begins to receive Android 5.1 update
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HTC One (M8) Google Play edition receives Android 5.1
Android 5.1 includes even more improvements to battery life. It also enhances the 64-bit ART compiler which should help your apps open faster. With the update, lost and stolen phones will not run unless the handset's owner types in his Google password. That goes even for phones that have been factory reset. Android 5.1 also adds stability to your device and improves RAM management. There are also some changes to animation and in the way the phone takes care of notification interruptions.
It seems that the update has just started to roll out, so it is possible that you might not receive it for a few days. When it does come, you might want to consider using a Wi-Fi connection when downloading and installing Android 5.1 on your unit. And you should have your battery recharged to at least 50%
source: XDA, Reddit via AndroidCentral
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