Resource support for tablets and mobile phones

I need to support an application for mobile phones mdpi, hdpi and xhdpi and 7 'and 10' tablets. I must admit that I am a little lost.

So far I just made a tablet version and what I did:

• one folder called "layout"
• 3 different folders called "drawable-sw600dp", "drawable-sw800dp" and "drawable-sw1200" containing images of 600 pixels in size, 800 pixels in size and 1200 pixels in size.

I got the impression that I messed it up and that I should have created the standard "drawable-mdpi", "drawable-hdpi" and "drawable-xhdpi".

But if I do this:

• In which folder should I put images for tablets? xhdpi only?
• how large (in px) should the images for tablets be?
• How big should the images be for mobile phones?
• and last but not least: how to name the “layout” folders in order to have a different version for mobile phones and tablets?

I have already read the Android recommendation as 1000 times and I'm still confused ...

EDIT 1

This paragraph on the Android website answered my question: "How to name the" breadboard "folders to have a different version for mobile phones and tablets?"

EDIT 2

As for the dropdown folders, for mobile phones it seems quite obvious that I need to create 3 folders in this way:

• drawable-mdpi containing 320 pixels wide images
• drawable-hdpi containing 480 pixels wide images
• drawable-xhdpi, 720

, .