[Huawei P20 Lite Guides, News, & Discussion] Zapthos:
So finally, Huawei has released the new EMUI 9.1 for the P20 lite! In this thread I will be doing a full review of this update. This will include: performance, battery life, UI, bugs & other things.

1) Performance

Personally, I feel like the performance is terrible now. The phone boots up faster and gaming works smoother: PUBG Mobile used to run at like 15-20fps with some lag spikes here and there, now it runs at 30+fps without random lag spikes! These are the settings used: graphics = balanced, style = realistic. These are the highest settings we can use on the P20 lite, but since this works so well they might bump it up to HD settings. This is due to the new GPU Turbo update. There was one before, but this one makes bigger changes. I do feel like the RAM usage is higher, though. The system itself is actually very laggy and the camera is unresponsive.

Update: After updating to 9.1.0.200, the lag has finally been fixed!

2) Battery Life

The battery life is better too. On EMUI 8.0 I had ~8 hours of SoT, which has increased to ~10 hours! That means 2 hours better battery life, which is 25% more.

3) User Interface

The UI has also got an overhaul. The notification panel is now white instead of black, we got a new task manager, a new font on some places, rounded squared icons, new icons in settings, a new recovery & a new boot screen (only difference is the 'E' in the Huawei logo). I personally really like this, but this is ofcourse up to your personal preference. What I am missing here is a dark theme. Not all dark themes will work like they should, but I'll get back on it on the bugs section.

4) Bugs

So there's one small bug: the themes. Normally if you apply a theme your icons from the notification bar should change too. This isn't the case anymore. It's not the fault of the 9.1 update (it's been here since the November security patch), but Huawei told some people that it should be fixed in 9, which it clearly isn't. Here's an example: on this theme, before the November patch, the statusbar icons would be the same as on stock Android, which isn't the case anymore. https://play.google.com/store/apps/details?id=emui.en.com.gpix2&hl=en_US it's not a big issue, but it can be annoying for some people (including me). Also the font colors don't change properly, this can be annoying for dark themes, because then you get black fonts on a black background, which you can barely read. Normally the fonts will change to a color depending on the theme.

5) Other things

One of the other changes is in the notch. Now, most apps actually stretch into the notch, instead of it having black bars next to it. Unfortunately, there's no option to change this, but some people including me actually prefer it like this.

If you have any questions about EMUI 9.1, just comment under this thread. Also I wanna say that you can find a lot of info about EMUI 9.1 on this thread: https://xdaforums.com/huawei-p20-lite/how-to/android-pie-update-status-huawei-t3836567

Edit 05-06-2019: There actually is a way to hide the notch for specific apps if you don't want it shown in fullscreen apps: Go to settings > display > show more options > notch > custom and hide notch for the apps you wanna hide it from. Sorry if the names are different, I translated it from my language to English.