Tony L., Dec 22, 2016 : Hi all, We are starting the incremental roll-out of OxygenOS 3.5.5 for the OnePlus 2. Here are the changes for this build. Here are some highlights: 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 Important: Clock, Calculator and Messages will be REPLACED by stock OnePlus apps if you have never updated the corresponding Google apps. But you can download these apps from Google in the Play Store even after the replacement. Many of the phone settings will be restored to default after upgrading to 3.5.5, for instance device name, ring tones, accent colours and status bar battery indication will all be reverted to default settings. After updating to 3.5.5, basic functions like WiFi connectivity, Network and Fingerprint might be affected if users flash back to 3.1.0. Users will have to use an intermittent version that will wipe all data from the phone. You should backup if you want to revert to older versions from 3.5.5 without losing data. Please refer to the updated guide here to perform the downgrade process: https://docs.google.com/document/d/1adh17i1Xrm2uo8DI4E7ykWc_8MS9vFF8zsVaQZaIVww/edit?usp=sharing For those who were on previous versions for the OnePlus 2, we appreciate your active feedback and attempts to reach out to us. With your help, we have been able to better optimize and improve several key areas. Thank you for your patience and as always, we look forward to hearing your continued feedback in the bug reporting forum here: https://forums.oneplus.net/feedback/. As this update will move you to the new Oxygen UI, please follow the link below for the UI/UX experience survey. We’d really appreciate a few minutes of your time, as it will help us make OxygenOS even better. - Feedback on UI/UX: https://goo.gl/forms/EOd2tSdFJI2N6xfD3 As always, this OTA will be incremental. The OTA will reach a small percentage of users today, and we'll begin a broader rollout in a few days. Your feedback is appreciated. We may not always be able to respond to every comment in the forums, but please be assured that we take your comments and feedback seriously. Hope you enjoy! ***Flashing guide for OnePlus 2: Downgrading from 3.5.5 to 3.1.0*** A few things to keep in mind before you start the downgrade process: This downgrade process will erase all data from your phone, please perform a full backup of your data before you start downgrading. Please ensure the device has enough power or charged in before downgrading. Basic functions will be affected if you skip step 3 and perform step 7 immediately. Steps: 1) Download 3.1.1 Intermittent Version and 3.1.0 Stable Version and copy them onto the phone’s directory. (Example: Storage/Internal Storage/Download) 2) Power off your phone and enter Recovery Mode by pressing the Power and Volume - button together for 3 seconds. 3) Choose English > Install from local > Choose OnePlus2Oxygen_14_OTA_021_all_1610121102_wipe_9505656273ba4203.zip from the phone’s directory. (Example: Storage/Internal Storage/Download) 4) Wait for the flashing process to complete. Do not cut off power and do not interrupt until the process is completed. 5) After the flashing, choose “Reboot” and device will restart. 6) Repeat Step 2 7) Choose English > Install from local > Choose OnePlus2Oxygen_14_OTA_020_all_1608262242_44a55e674a2b4bf6.zip from the phone’s directory. (Example: Storage/Internal Storage/Download) 8) After the flashing, choose “Reboot” and device will be downgraded to 3.1.0. ****Status update: Network issue is still being reviewed and for users who are affected by IMEI issue, we are drafting a plan to resolve this. We apologize for this and please be patient while we get them fixed. Never Settle.