Straus, I really have no bone to pick with you. My recent posts to you about the Back button has little to do with me liking Android more. It has everything to do with explaining to you what the Back button does.
As for the "published description," I've already addressed that in this post:
https://forums.macrumors.com/posts/18059331/
The member that quoted that was interpreting it wrong. I even used Google's own apps to demonstrate it and offered a more comprehensive list of functions of the Back button. Even the member that quoted it dropped it after reading my post. You may have quoted my post, but did you actually read it? Cause you're certainly not addressing anything in it.
I've explained everything you brought up about the Back button, including why sometimes it does seemingly switch between apps. Again, I've provided you details in terms of the Back button's functionality. This one being the most pertinent one:
-Return to previous app when on the last activity and the app was launched through intent from another app
Again, it's not a mere coincidence that once you hit a link, then suddenly the Back button is "working properly."
And you've still yet to answer my most important question: How would you ever go back within an app after you've switched to it if the Back button takes you back to the previous app? I have no idea how you'd navigate backwards in the app you've just switched to if the Back button did what you wanted it to.
It works properly.
As I've said before, the inconsistencies with the Back button itself can be fixed (the one I experience once in a while are apps that take you Back to the home screen when there's still more "back" to go back to within the app). This can be improved and made more consistent. Ultimately, it isn't so big of a problem that I wish they got rid of the Back button -- it's still a better form of navigation than not having a Back button, IMO.
Your definition of "working properly" means it's an App Switcher. I don't know how to make this any clearer: it's not an App Switcher. There's already an App Switcher button.
Re-read my previous post (and maybe actually respond to the points and explanations I made?).
Otherwise, I'm sorry you don't understand how the Back button works.
EDIT: Straus, here's one more example for you. I hope you'll address it:
In your scenario, imaging you start at the Home screen. You launch an App (say the Play Store). If the Back button did what you wanted -- that is, if the Back button takes you back to the previous screen even if it's a different app -- the previous screen would be what in this scenario? It would be the Home screen, correct?
So in your world, going from Home screen to Play Store, then hitting Back should take you back to the Home screen. I ask again, how in the world would you navigate backwards within the Play Store app, then? What about the apps that don't have the upper-left back navigational button? You'd essentially be stuck forever in the current screen of that app? How does that make any sense? (It's same question I've asked you repeatedly when using the App Switcher; how would you navigate backwards in the app you've switched to if the Back button sends you to the previous app? You'd be stuck forever in that current screen of the new app, too?)
If the Back button returns to the previous screen, no matter what it is, then the Back button is useless inside an app unless you go forward within the app first -- this makes no sense. At all. And it undermines the point of both the Home and the App Switcher buttons.
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It's all there. I've explained it multiple times in multiple ways. He wants the Back button to do something else.
The Back button has never ever worked the way he's describing, and it never will, thankfully.
I don't know how else one would go backwards within an app after switching to it if the Back button brought you back to the previous app. It just makes no sense. You'd be stuck in the current screen of the new app forever. Absurd.
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Great idea. This would be along the lines of what I suggested, a more dynamic Back button. That's how you'd improve the Back button.