How to ask the user to change default apps

Question

I want to prompt the user to select what app he wants to be his default. (in this case, it's between my custom launcher, or the android standard launcher)

I've been lurking around Google, Stack Overflow and Android API Docs for the past hours hoping to find a solution for this.

I think I've managed to gather quite a bit of information so far, but please correct me if I'm wrong:

1. An app cannot make itself the default app
2. An app cannot stop other apps from being the default ones (other that itself)
3. The only way to counter point 1 is through addPreferredActivity() method, which was deprecated
4. There is a workaround, that involves creating a fake activity. However, it appears like it stopped working after android version 4.4.2

Also, most of the info I found on this subject was over 4 years old.

I've successfully implemented the workaround stated on point 4, but I'm afraid it might not work with android versions past 4.4.1

So, here's my question:

How can I prompt the user to change the default app?
(Keep in mind there's probably already another app set to 'Always')

Here's an example of what I'm talking about:

Thanks in advance!