The OnePlus team just handed out OnePlus 2 users a Christmas gift in the form of OxygenOS 3.5.5 OTA update. Even though it’s not Nougat release for OnePlus 2, users are still gonna love this the 3.5.5 update to OxygenOS brings VoLTE support to the device, a godsend feature for Indian OP2 users who are dying to use the device on Reliance Jio which requires VoLTE support.

The OxygenOS 3.5.5 update is based on Android 6.0.1 Marshmallow, while the OnePlus 2 Android 7.0 update remains scheduled for release sometime in February 2017, as for now, the OnePlus 3 and OnePlus 3T are up for Nougat this month.

The OxygenOS 3.5.5 update also brings other cool features, like App Lock, Battery saving mode, Gaming mode, while adding few tweaks to Alert Slider (additional options), Volume adjustment bar (redesign), Shelf (optimizations), Clock App (UI), and a UI makeover at some places for the OxygenOS OS itself.

The OnePlus 2 OxygenOS 3.5.5 build also installs the latest security patch from Google, for the month of December, which improving on the system stability and fixing general bugs.

Note that, the OOS3.5.5 update will remove the OnePlus’s stock apps in Clock, Calculator and Messages, and will replace them with Google’s stock apps respectively. Some of the settings on your OnePlus 2 will be reset too, like ringtones, accent colors, device name and status bar battery indication.

OnePlus is working hard on the Nougat update, and released the Open Beta 9 build for OnePlus 3 recently, while the OnePlus 3T Nougat update OTA just got leaked out yesterday.

Full Changelog

  • Enabled VoLTE functionality for select carriers
  • Added App Lock
  • Added Battery Saving Mode ( Settings > Battery > More )
  • Added Gaming Mode ( Settings > Developer Options )
  • Added Additional Options for the Alert Slider.
  • Redesign of the Volume Adjustment Bar
  • Shelf Optimizations
  • Updated OxygenOS UI
  • Updated Interface and UI of the Clock app
  • Updated Android Security Patch Level to 1/12/16
  • Increased System Stability
  • General Bug Fixes

Moreover, in case you don’t come to like OxygenOS 3.5.5 update, and want to roll back to OxygenOS 3.1.0, then you will have to download a separate special package OnePlus made available today. That’s a must if you want to go back to OxygenOS 3.1.0. Download 3.1.0 here, where you also get a guide to install special 3.1.0 downgrade firmware.

Download OxygenOS 3.5.5 OTA for OnePlus 2

Download the OTA file of OnePlus 2 OxygenOS 3.5.5 update from below. And install it using the guide given below that.

→ OnePlus 2 OxygenOS 3.5.5 OTA
OnePlus2Oxygen_14_OTA_026_all_1612220228_c351fee.zip

How to install OxygenOS 3.5.5 update on OnePlus 2

Note: You’ll need a stock recovery installed on your OnePlus 2.

Step 1. Setup ADB and Fastboot on your PC.

Step 2.  Download the OTA update .zip file on your PC and rename it to ota.zip.

Step 3. Enable USB debugging:

  • Go to your phone’s settings » About phone » and tap “Build number” Seven times. This will enable Developer options on your phone.
  • Now go to Settings » Developer options » and tick the USB debugging check box.

Step 4. Connect your OnePlus 2 to PC.

Step 5. Now open the folder on PC where you downloaded the ota.zip file and then open a command window inside the folder. To do that, do a “Shift + Right click” on any empty white space inside the folder and select “Open command window here”from the context menu.

Step 6. Now issue the following window to command window to reboot your device into recovery mode:

 adb reboot recovery

└ Check your phone’s screen, if it’s asking for “Allow USB debugging”, accept it by selecting OK/Yes.

Step 7. Once in recovery mode, use Volume buttons to navigate up and down between options and Power button to select an option.

Step 8. Select the “Install from USB” option. on the device,

Step 9. Now issue the following command to finally begin installing the OTA:

adb sideload ota.zip

└ This will begin the OTA installation.

Step 10. Once the OTA zip is installed, select reboot from the main menu of recovery to restart the device.

That’s it. You successfully installed the OxygenOS 3.5.5 update.