Creation of android or ios smartphone application with bubble

Hello everyone, I am French, so excuse me for the bad translation.

As said in the title, I am interested in designing applications for phones.

I know that bubble.io provides a version to create native applications for phones, but I do not have access to early access.

So after looking at several examples, it is advisable to build your mobile application in bubble on a single page, and check the box “this page is native app” in appearance.

then you have to create several groups that are one on top of the other and that you make visible or not depending on the interaction with the user, from what I’ve read it’s about creating views instead of creating pages as you would do in a website

it is also advisable to size this page in 320X640
and it will enlarge according to the screens of each phone or tablet

my question is: how should this page be configured at the container layout level?

I did some tests by setting the container layout to align to parent
and it seems to work but I’m not sure

then for the groups that I place one above the other, I uncheck “make this element fixed width” and “make this element fixed height” so that they expand according to the screen

is this way of doing things good or not because I’m not sure that the responsive works correctly by acting in this way, thank you in advance for your answers