Multitasking has been an elegant proposition since it was introduced to Windows Phone. To actuate it, simply hold the back button, and several of your previously used apps will appear in a horizontal list. This is called the app switcher. It's a great implementation with no discernible faults.
And yet, for some perplexing reason, it's a little bit worse in Windows 10 Mobile.
In devices like the Lumia 950 and Lumia 950 XL, holding the back button takes appreciably longer to activate the function. This speed differential is similar on my Windows Phone 8.1 Update 2-powered Lumia 640.
I honestly cannot fathom why this is even an issue. There's no underlying hardware deficiency, as the user is simply pressing in the touchscreen itself on devices like the Lumia 950 and 950 XL. The only thing I can think of would be that Microsoft believed many were actuating the multitasking function on accident by pressing too long. An explanation I really don't buy.
This is sort of like the changing schematic of the music discovery function, as I discussed in the music discovery dissection a few weeks ago. Change for the sake of change, for no discernible reason.
I realize this is a non-issue to many of you and isn't really a big deal. But as someone who appreciates well-designed software that just works like it should, it irks me. It takes away some of the fluidity I've come to enjoy as a signature quality of the Windows Phone series of operating systems. To me, it's the equivalent of shifting to from R to D in an automatic gearbox, and having to wait a second or so before the wheels actually start to turn forward.
Not the end world. But a completely unnecessary change to previously sensible behavior.
This examination was done with OS build 10586.29 and firmware revision 01078.00027.15506.02004, which is currently shipping and updating with the Lumia 950. This Lumia 950 is not in the insider program.