The "killer app" for smartphone refresh rates staying low are (1) battery degradation and (2) forced OS updates for app updates, which in turn slows the phone down to compel an update[1].
[1] I'm actually curious if OS updates slow down older phones these days. This was the case 5 years ago but perhaps things have changed/
It was hobbled at the outset with 2GB RAM. At introduction performance was adequate. It has degraded since then. There are times when I exit an app and it takes several seconds before the home screen is populated. Navigation normally runs in the background but if I open a different app, it may get bumped and disappears from notifications. I listen to podcasts frequently and its background process (the part that keeps audio going if I open other apps) gets bumped.
These are not related to processor horsepower but I believe are symptoms of insufficient RAM. It could also result from additional installed applications, but I have uninstalled more than I have added and it seems not to improve.
Maybe it's time to look at third party ROMs.
Towards the end of its life its performance had degraded to the same point you experienced. Multiple seconds for the home screen to populate, camera lag, etc. It's crazy that a cell phone with 2GB of ram is incapable of running recent versions of Android with decent performance and even crazier when I'd open up a task manager and see mandatory things like Google Play Services consuming almost 60% of the ram on the device.
Short support cycles seriously dent the feasibility of keeping the same phone for even two years...
- Devices that support Verizon's bands & CDMA are mostly only sold as Verizon branded devices. (CDMA is less important every year but I still occasionally need 3g)
- ~All Verizon phones have locked bootloaders and no official way to unlock them.
- Manufacturers don't make the easy mistakes which let you unlock their bootloaders anymore.
I will not be a Verizon customer for much longer.
Advantage is that you buy for half the price of a new flagship.
Things will always improve, but for cameras, we are getting to the point where if your smartphone camera isn't good enough for you, you are probably at least an enthusiast and you probably want to get a real camera.
Since then, I've seen absolutely no game changing improvement.
On the Android side, it's sorta debatable whether Google Services is really part of the OS or not, but in any case, a Galaxy S4/5 with the latest google SW is a performance disaster. Maps regularly freezes for like 3-5 seconds at a time; its sluggishness is almost certainly causing additional auto accidents. Pretty much every other G app takes more than a second to open, despite being compiled-to-native-code during installation. Disabling airplane mode will cause 100% CPU on all cores for like 15+ seconds. Performance was certainly better when the phone was new 4-5 years ago.
[1] http://money.cnn.com/2017/12/21/technology/apple-slows-down-...
The said that as the battery degrades, they limit CPU spikiness that can abruptly kill the device even with a non-trivial amount of juice left.
That's not nearly the same as "slowing down the phone with every upgrade".
Often people have reported better performance after an OS upgrade, although obviously results may vary, and subjective impressions are always, well, subjective.