Now root is available for Htc One A9 but to root your device you have to unlock the bootloader of Htc One A9.If you haven’t unlocked the bootloader yet then follow this guide–»How to unlock HTC One A9 Bootloader

Device that is supported

Right now, root is available only for AT&T One A9 Check your model number don’t try this method on different variants

Warning:

rootmygalaxy.net will not be held responsible for any kind of damage occurred to your AT&T Htc One A9 while following this tutorial.Do it at your own risk. Follow the guide below to Safely Root AT&T Htc One A9

Downloads

Modified boot image a9-att-635081.3.zip — Link → Make sure you download the right boot image whose filename contains build info as found here: Settings > About > Software Information > More. TWRP recovery — Link → TWRP is semi-working, but it’s good enough to root A9 using guide below. su.zip — Link superuser.zip — Link Full Step by step guide to Root AT&T Htc One A9

How To Safely Root AT&T Htc One A9

Step By Step Guide

To verify the root status install Root Checker. Source

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