I have a Nexus 5X that was 2 years old late last year. At that time I git it's last major OS upgrade. (It will continue to get security updates for another year or so.) This is as good as it gets in the Android world.

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.

I had a 5X that I recently replaced due to the common boot loop failure.

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.

Could it be a case of degraded battery like the iPhones? If the battery can't supply enough current, the system has to slowdown to avoid a hard crash.

As a grumpy Moto G 3 owner, I would love for an OS update that slowed my phone down.

Short support cycles seriously dent the feasibility of keeping the same phone for even two years...

Switch to LineageOS. The Moto G series is well supported up to Nougat. It will not be any slower either.

I assume aftermarket ROMs are a non-option for you?

As a Verizon customer:

- 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.

Depending on your device, installing an aftermarket ROM can range from "easily accomplished from initial query in a search engine to ROM installed within 1 hour" to "I am stuck in a nightmare of poorly written, contradictory forum posts written in a mishmash of languages with lots of instructions that say 'this is easy, but WARNING COULD BRICK YOUR DEVICE'." Who has the time or patience for such confusion?

I've been doing a variant of the 3 year cycle: buy a year old model (e.g. I bought an S7 just after the S8 came out), and then keep it for 2 years (it's even possible I'll be able to keep this one longer. It's not feeling slow yet).

Advantage is that you buy for half the price of a new flagship.

for me the camera is one major reason to upgrade every 1.5-2 years. But I buy a phone(asus) that is at least 50% cheaper than most of the high end phones so I figure I'm coming out ahead. They probably have better cameras but mine has been good enough until the next refresh cycle

For me, cameras have become good enough in around 2014, before then, smartphones cameras tended to turn low light pictures into a blurry mess.

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.

> if OS updates slow down older phones these days

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.

I have an iPhone 6S - I'd say OS updates do slow the phone down, but they also tend to be really buggy and generally rubbish for a while. I think it's probably more bad engineering and software quality than anything nefarious.

My experience with Android is the opposite, it's gradually better and faster with every release.

Apple is intentionally slowing down phones with every OS upgrade to "preserve the battery" [1].

[1] http://money.cnn.com/2017/12/21/technology/apple-slows-down-...

That's not at all what they said.

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.