Ionic 4 - App looks different on real device

Ionic Framework ionic-v3
1

Hi!
I’m struggling with the styling of my Ionic app. I’m running iOS and Android simulators and styled the app accordingly. When I’m using the DevApp or deploy the app to a real device (only tested on my HTC U11 for now), the app looks completely different.

Here’s a screenshot of the Android emulator (and how I want the images to look):

689×1422 108 KB

And here’s a screenshot of the app running on my real device:

1440×2560 287 KB

A similar problem occurs when I try to set a height of let’s say a card, to take 50vh of the device. Everything looks good on the emulator(s), but not on the real device.

Can anyone give me some hints how to get the app looking as I expect it to be on actual devices?

Thanks in advance