I've had the iPhone 6S Plus for over a year, and I'm so happy I didn't upgrade to the iPhone 7

The iPhone 6S looks nearly identical to the iPhone 7, save for the redesigned and less visible antenna stripes. The plastic stripes might bother some, but I dress my iPhone in a case, so I can't see the stripes anyway.

While the iPhone's 7's jet black, matte black, and new red options are nice, they have no effect on my desire for the iPhone 7. If I were to buy a new iPhone 7, it would be the white/silver model.

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One of the main reasons I upgrade to the latest smartphone is to make sure I can run my apps quickly. In my opinion, there's nothing worse than waiting for an app to open and run — especially Google Maps when you're in a hurry.

The A9 chip turning the wheels inside my iPhone 6S Plus still feels speedy, and it rarely stutters while opening and running my apps.

The iPhone 7 Plus got a significant camera upgrade in the form of a dual-lens camera. It can zoom without losing photo quality, and the Portrait Mode feature adds that fuzzy, out-of-focus texture from professional cameras, called "bokeh."

The zoom is a meaningful upgrade, as my iPhone 6S Plus photos will look worse and worse as I try to zoom in with the camera app. But I'm not about to spend $800-plus on better zooming, and Portrait Mode is a mixed bag. Some like it; others weren't so impressed.

For the extra $800 in my bank account, my iPhone 6S Plus takes photos just fine.

The iPhone 7 has a slightly brighter display that can show slightly better colors with its "wide color" feature. Yet I haven't craved a brighter display with better colors on my iPhone 6S Plus. And both phones have Apple's 3D Touch feature, which lets you press an item to bring up a menu of useful shortcuts.

I quite like the new home button on the iPhone 7. It's a capacitive button that you don't have to physically press, and it feels more modern compared with the iPhone 6S's mechanical button.

But it's not an upgrade worth spending more money on. The mechanical button on my iPhone 6S Plus works just fine, and it can read my fingerprint to unlock my phone or make mobile payments with Apple Pay just as quickly.

I'm fully on board with Apple's vision of a "wireless future," as my tech arch nemesis is the cable. At the same time, I own a pair of wired headphones as a backup to my Bluetooth headphones, and there have been several instances when the headphone jack in my iPhone 6S Plus has come in handy.

Sure, I could still use wired headphones with the iPhone 7, but only if I have a dongle or if my wired headphones have a Lightning connector, neither of which is as convenient as the good old headphone jack.

I'm a little worried that I'll have to adjust to using a dongle, which I'll surely lose, when I buy my next iPhone — if it's an iPhone.

The iPhone 7's water resistance is a big deal because the phone is less prone to damage if you drop it in water accidentally.

At the same time, I've never dropped my iPhone in water. (I'm literally knocking on wood right now. Look, here's a photo of me knocking on wood, taken with my iPhone 6S Plus.)

Also, the iPhone 6S is (unofficially) somewhat water-resistant, which should be enough for minor splashes and drops, even if it's likely not as water-resistant as the iPhone 7.

The only time I'd upgrade to an iPhone 7 would be if my iPhone 6S Plus succumbed to water damage.

I'll keep using my iPhone 6S Plus until it can't keep up with me. That could potentially take it beyond the iPhone 7S, or even the iPhone 8/10/X edition, or whatever Apple will call its rumored fancy new iPhone. We'll have to see what Apple comes up with this September when it'll likely announce its new iPhones.

At this point, if you have an iPhone 6 or older and you can manage another six or so months with your older model, you could wait for the iPhone 7S or the new model.