I preordered a 14 pro on launch and have had it since. This was an upgrade from the 7 I had at the time for 2.5 years at the time given by my parents when I was a teen (before then, my first phone was a five for almost two years, then I cycled between two used 6's and two used 7's, holding onto that last 7). Now it's gonna be four years of the 14 pro in September. When I got it, I made my goal to hold onto it for six years and I'm pretty sure I'm on track. At the time, I loathed the idea of some people paying every year or two for a new iPhone, but at the same time, I consider myself an Apple enthusiast and loving new Apple tech and keep track of it through leaks throughout the whole year. Currently my phone is at 79% capacity on its original battery, has barely any scratches of any kind, is on its second case as of about nine months ago, and I'm constantly on the developer beta, which probably heats it up and wears away the battery quicker. I think I'm ahead the curve, but I'm considering replacing the battery.
My main concerns are the following: 1) If I replace the battery now, sure I'll benefit, but by the time I upgrade it'll degrade again and resale value would tank again. It makes sense, at least in my mind, to upgrade even further out than 6 total years if I replace it now, or if I stick to 6 years to just power through it. 2) When I originally set the goal of 6 years I based it on a; six years between my original 7 coming out and the 14 pro coming out, and b; that same 7 got cut off software wise and wasn't getting iOS 16 (my current phone's software on launch, working out pretty nicely), which means it got 6 years of software support since it came out. However, iOS 27 supports all the way back to the iPhone 11, meaning a phone from 2019 will be supported until at least Fall 2027, which equates to a whopping eight years of software support! Should I hold on to my 14 pro even longer because of this, assuming it still functions? That would make the upcoming 4 year mark the exact halfway point to replace the battery.
I also ask myself the question if it's worth the new features to just upgrade sooner. For example, my phone is the last lightning iPhone, which will continue to get more difficult. It's also the last pro iPhone without getting Apple Intelligence, meaning every new iOS I have to see that many of the new features will not apply to my phone. (It's also the last stainless steel iPhone, but if anything that's just extra weight and sharper edges with only a slight durability benefit) If you were me, would you let this get to you? Or would you make do on the vow when you bought it of just treating any new feature post 14 pro as part of a sum of features all adding up to when you buy when you said you would? Obviously when I watched keynotes since, I'm still wowed by new features, but I've kept myself from buying by telling myself it's all adding up to when I upgrade further down the line. But sometimes I feel like I picked a year to upgrade that didn't age all that well compared to even the one right after it. Any potential advice isn't expected, but greatly appreciated.