android
T-Mobile HTC One M9 To Receive Android 5.1 Lollipop Update
The update will come in the form of build 2.7.531.6 via Over The Air (OTA), and it will be a rather hefty 833MB download, which means you would be better off connected to a fast Wi-Fi network to get the job done as opposed to relying on your data. If you haven’t yet received Android 5.1 Lollipop, just head on to the About > Software updates menu from time to time until you pick up the download prompt.