I made a pretty gif:

Pretty proiud of it!
(Used http://gifmaker.me/ ...)
Source pictures:


Yea, this is something people will have to live with for now, unfortunately. It's not possible to use the same scaling algorithm _exactly_ for the launch screen image as for showing it later as a drawable. It's annoying but it's a tradeoff. I misplaced the issue that talked about why this is.
I had the same issue on my Nexus 5X.
I changed the scaletype to FIT_XY in Splash.java. I don't have this effect anymore.
@arnaud-zad you deserve a cookie, that fixed the glitch for me too respectively changing the following in Splash.java fix it
from
splashImage.setScaleType(ImageView.ScaleType.CENTER_CROP);
to
splashImage.setScaleType(ImageView.ScaleType.FIT_XY);
@mlynch if you are agree that that could be the default, I could provide a PR, let me know
My only concern with that is if people have splash screens that aren't the exact right size, but I suppose that shouldn't happen. Yea, I'd be open to that
@mlynch I guess most of the people gonna generate their splash with a tool and therefore there is a chance that the images will be often the right size, but well only my guess
Anyhow cool if you are up to, there you go the PR https://github.com/ionic-team/capacitor/pull/929
Closing as #929 has been merged.
@mlynch this still seems like a problem. With a new capacitor project the splashscreen still is distorted. This screenshot is from a Pixel 2 XL:

Reverting the FIT_XY change displays the splashscreen correctly, but still shows the distorted one when launching the app. The only way I see around both of these issues is to use a 9 patch image for the splashscreen: https://developer.android.com/studio/write/draw9patch
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@mlynch this still seems like a problem. With a new capacitor project the splashscreen still is distorted. This screenshot is from a Pixel 2 XL:

Reverting the FIT_XY change displays the splashscreen correctly, but still shows the distorted one when launching the app. The only way I see around both of these issues is to use a 9 patch image for the splashscreen: https://developer.android.com/studio/write/draw9patch