I am not stretching it. I run the current iOS version on a 4s purchased in 2011. Battery is still working pretty good too. Not as good as when it was new, but the whole thing still works as my only phone without much issue.
You're right, I'm runnin 9.3.5, just checked. I thought I was running 10. Regardless, the 4S has been a true workhorse and I don't think Apple makes them this robust any more (obviously, Apple lost money on me by making such a reliable phone that I didn't need to replace it!).
