I can't really comment on tablets other than iPads, I do have an Asus 'droid, bought as a backup to my iPads for when I'm using my X32 but I haven't got to grips with it yet (and probably never will TBH as I have just bought a 3rd iPad, a mini2). My first iPad2 is 4 years old and works just fine. Battery life is good and aside from a small scratch on the screen it looks and works virtually like when it was new. My son seems to upgrade his 'droids and computers on a two yearly cycle (though he'd do it sooner if he could).
I can also comment on Apple Mac computers and my experience with them has been rather better than with MS products post XP (the best OS Microsoft ever produced). They're not perfect but, compared with the issues I've had to deal with on recent PCs belonging to my wife and and my best buddy they just work, straight out of the box. The MacBook Pro I'm typing on as I speak is 4 years old and still feels and looks pretty much like new, battery life is a little shorter than it was (around 20% down) and it doesn't feel quite as fast as it used to but, apart from a failed Seagate HDD a couple of years ago I have had to do nothing to it. Given that my previous two laptops had a battery life of 30-40 mins and 90 mins respectively when new, felt cheap (even through they were't) in comparison to the MacBook and both died in less than 3 years (and that's before I talk about Windoze), I won't be going back to windows based machines anytime soon.