The upgrade to Android Pie brought a lot of improvements to the Android system, such as optimized system performance, Adaptive Battery, and more. Some of the changes have been polarizing, such as the new horizontal recent apps overview. Some people deem the new recent apps switching UI a regression and harder to navigate. If you're on the OnePlus 6 running OxygenOS Open Beta or OxygenOS 9.0, there's an easy way to go back to the way things used to be - and without root as well.

All you need to do is download an older version of the OnePlus Launcher and replace the current version you have on your device with it. You'll also need to use a third party launcher to replace it.

How to bring back Vertical Recent Apps on the OnePlus 6

Credits go to /u/Dwdization on Reddit for this trick!

Step 1 - Download a third party launcher

You'll need to download a third party launcher, as when we install the older OnePlus Launcher later on you won't be able to use it, as it will crash. The third party launcher that I am using is the Rootless Pixel Launcher by AmirZ, but you're welcome to use any others such as Lawnchair, Nova Launcher, Action Launcher, etc. Just be sure to set it as your default launcher.

Step 2 - Install an older version of the OnePlus Launcher

Next, uninstall updates to your current OnePlus Launcher, then download an older build of it from APKMirror such as this one.

Conclusion

You're done! How this works is pretty simple, as it's a change in how Android Pie works with its recent apps switcher. The app switcher code is now built into the launcher, so switching back to an older build of the system launcher means that the system is no longer able to draw its recents menu from the OnePlus Launcher. As a result, it falls back to the system in-built one that we all know and love from Android Oreo. The only problem is that the OnePlus Launcher then fails to work as it's made for Android Oreo, and will force close when trying to use it. That's why we need to use a third party launcher.