iphone 6 - for how long will there be OS upgrades?

Often it's a few years down the line, but can depend on the particular model. At this point it's likely that iPhone 6 will probably get at least the next 2 major iOS versions, and perhaps more than that. However, the fact that it has 1 GB of RAM, compared to iPhone 6s and later which has at least 2 GB of RAM, that can play a role as to how long the device might be supported and how well it will do with newer updates.

If you can, you are probably better off at least getting a 6s (or perhaps SE) if you can get a good deal. But if the deal for a 6 is pretty good it's still a worthwhile device to have that will still be supported by updates for probably a couple more years.

 

It would certainly be more future-proof and more or less somewhat better overall than a 6 (aside from basically a smaller screen).

 

I have an iPhone 4s running iOS 9.3.5 and I just updated an iPhone 5 to iOS 10.3 yesterday. If that tells you anything.

 

If that is addressed to me, my point is that those devices are old yet running current or nearly current versions of iOS.

The iPhone 5 started with iOS 6. So, four versions of iOS later it's still being supported.

The 4s I have stopped, being supported at iOS 9.3.5, but the first version it ran was iOS 5.

The 6/6+ launched with iOS 8. If four versions of iOS is the standard, then, you're good until at least iOS 12.

 

They have started selling new iPhone 6 models in some countries around the world. Probably to meet a price point in a larger size than the SE (and likely where the LTE bands are sufficient. Here in the US, a new 6 isn't good for T-Mobile).

Rumor is that they are dropping iOS support for the 5/5C this year. So a 6 might be 2 years down the road. The 5S is the oldest 64 bit compatible model. But since the SE has the same size of screen, no real rush to drop support for the 5S since Apple wouldn't be simplifying screen sizes.

 

IOS 13 is my guess

 

iOS 12. Not counting the iPad 2, I think Apple reached a limit of 5 total iOS versions for each device going forward.