How long has your iPhone lasted for?

I just got an iPhone 5S that was my grandfather's phone (he pasted away a couple months ago). I have an iPod Touch 4th Generation and it is dying. It made me wonder how long the iPhone will be around for.

Does anyone have a guess on how long iPhones last for? I know it depends on the device and how well it's been taken cared of, but hearing your experience with your own iPhone would be helpful. Thanks!

Added (1). I know that the iPhone 5S is 4 years old, and my iPod Touch is 5 years old if this helps.

5 years

5s lasted for four years before it got laggy

I've had mine for about 13 years now

I usually keep mine for 2 years, but my 1st was for 4 years & was fine.