Well, who knows who's doing what and why, with all the money at stake. But they throw crumbs of API additions and obsolete older gear, programmers don't get paid to maintain long term programs. There's no a priori reason for the constant version push, we're just dumb meat.
Security my butt. None of this stuff is even remotely secure. I misdialed someone's number once with some extra digits and suddenly I was listening to him and his friends talking. The phone never rang. That was a bit of an eye-opener. The cameras are on tap too. Our great-grandchildren won't believe we paid (!) to be monitored and to feed the advertising machine 24x7.
The one security feature that matters is being able to pull the battery when you want privacy. And THAT is just one advance that newer phones have lost, and my Note 3 has, and why I keep it. New batteries cost like $20, an impact-resistant case costs $10. Of course it runs fine, and I'm angry to have to start looking for a replacement.
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