Is iOS 12 still supported?

Now that iOS 13 is out, and iPhone 5S and iPhone 6 won't be getting it - does this mean that the phones are no longer supported?

Should these devices be considered past their end-of-life? I know that Apple released a iOS 12 security update alongside iOS13, but will that continue to happen?

Is there a way to find out the security status of each iOS/iPhone release?

There's a difference between hardware support (new battery, replacement screen, etc) and software support.

Typically, Apple provides hardware support for 5 years after manufacture on their products.

The iPhone 5S is not currently listed as 'vintage'. However, it's possible the list may be updated shortly, as the phone was discontinued 5 years ago. The iPhone 6 was discontinued 2 years ago, so will still receive hardware support until 2022.

As for software support: obviously, the devices will not be offered new OS updates, but in the event of a major security flaw, they may receive a patch to fix the problem.

The phones will of course continue to work as they are. Apps will not be updated if they require newer OS versions than are present.

iOS 10 was officially released on September 13, 2016.

iOS 10.3.3 was released on July 19, 2017.

iOS 10.3.4 was released on July 22, 2019

iOS 11 was officially released on September 19, 2017.

iOS 11.4.1 was released on July 9, 2018.

[iOS] 12.0 was [released] on September 17, 2018.

iOS 12.4.1 was released on August 26, 2019

So we can't tell what Apple does or what it will do, but iOS 10.3.4 was released after iOS 11 launch. While iOS 11 updates ended with iOS 12 launch. And iOS 12's fate is yet to come.

You can similarly see what happened with previous iOS's and just assume that policies remain the same, or hope that they change for the good.

^{Sources: ●https://en.wikipedia.org/wiki/IOS_10#10.3.4}

^{●https://en.wikipedia.org/wiki/IOS_11#Updates}

^{●https://en.wikipedia.org/wiki/IOS_12#Introduction_and_initial_release}