We've crowned the OnePlus 7 Pro the best smartphone in 2019 so far, and that's largely due to its big, beautiful 6.67-inch QHD+ 90Hz OLED display. While its camera quality can definitely be improved, the new OnePlus flagship definitely has the best display out there. In Display settings, you have the option to choose between the 60Hz and 90Hz refresh rates, but the 90Hz mode actually changes to 60Hz for videos, the camera app, and phone calls. Furthermore, Redditors on /r/OnePlus discovered that not every web browser runs in 90Hz, suggesting that there could be an internal whitelist of some sort. Fortunately, there seems to be a hidden setting to force every app on the OnePlus 7 Pro to run at 90Hz. Here's how it works.

XDA Recognized Contributor C3C076, the developer of the popular GravityBox Xposed Module, was developing a Quick Setting tile to switch the screen refresh rate when he discovered that there are actually 3—not 2—refresh rate modes in OxygenOS. The 60Hz mode in the Screen refresh rate settings makes the device run at a constant 60Hz like most other smartphones, but the 90Hz mode is actually internally the "auto" mode. Lastly, there's a third, hidden true 90Hz mode that enables 90Hz at all times in all apps.

Screen refresh rate settings on the OnePlus 7 Pro.

To change the refresh rate mode to this hidden full-time 90Hz mode, you simply need to enter the following ADB command:

        adb shell settings put global oneplus_screen_refresh_rate 0
    

Once enabled, both toggles in Screen refresh rate settings will become unchecked and the option summary text in Display settings will show "60Hz" - but that's just a bug because OxygenOS doesn't expect users to be able to select this hidden refresh rate mode. To revert back to one of the officially supported modes, just change the toggle in Display settings.

We confirmed this trick works by comparing the results of the UFO Test on two browsers that don't support 90Hz on the OnePlus 7 Pro: Brave Browser and Samsung Internet. When the Screen refresh rate toggle for "90Hz" is enabled, UFO Test reports that Brave Browser and Samsung Internet are running at 60Hz. However, with the hidden, true 90Hz mode enabled via ADB, both browsers are reported to be running at 90Hz. Anecdotally, apps like Facebook and Twitter don't seem to dip to 60Hz when scrolling past a video.

How the OnePlus 7 Pro's Auto-90Hz Mode Works

We reached out to OnePlus for a comment on this hidden refresh rate mode and why not all apps use 90Hz. While the company didn't have an official statement for us, they did tell us that they don't recommend using 90Hz at all times because of the limited benefit it brings at the cost of higher battery use. They also informed us about how they determine when to switch between 60Hz and 90Hz.

According to OnePlus, large-scale games (with the SurfaceView), videos, and the camera will use 60Hz, while other scenes will use 90Hz. If an app uses SurfaceView, TextureView, or NativeActivity, then the OnePlus 7 Pro will run at 60Hz. However, there are special cases like the Google Chrome browser that uses SurfaceView, but can still be viewed in 90Hz. Also, there are certain games that are compatible with the 90Hz refresh rate, though we don't have a list of such games available.