The one thing Apple must do to keep me as an iPhone customer

OK, Apple, cards on the table.

I've been an iPhone user since the beginning. I've owned every model through the 4S, upgrading on an almost annual basis even though it meant paying extra. (Ah, the joys of the AT&T contract and its early-upgrade penalties.)

Why no iPhone 5? That little bit of extra screen-estate and slightly improved camera weren't enough to loosen my wallet, and so for the first time I held tight to last year's model. My 4S is soon to celebrate its second birthday, at which time I'll be out of my contract and free to make a move.

On September 10, you're probably announcing something new. Most signs point to an iPhone 5S, which, if the 4S is any indication, will be an iPhone 5 with a few extra gewgaws -- a fingerprint scanner, perhaps, and maybe a gold finish and 128GB storage option.

To my thinking, those would be some pretty underwhelming improvements. In fact, if that's it, then that's it: once again I will not be upgrading. Rather, I will probably do something I once considered unthinkable: switch to Android.

Why unthinkable? Because I love my iPhone. For all its shortcomings, I love iOS. And all my media is woven into iTunes. Sure, I can move nearly everything over to Google, but that's a hassle I'd rather avoid.

However, unless the iPhone 5S (or some supersecret other model waiting in the wings) offers one key feature, I feel almost forced into making the switch.

Bottom line: If Apple wants to keep me as an iPhone customer, it must release a model with a bigger screen. I don't mean a hair longer; I mean bigger.

See, right around the time my 4S turns 2, I'll turn 45. My eyesight ain't what it used to be, and a 3.5-inch screen just doesn't cut it anymore. (Nor would an iPhone 5's 4-inch screen, which is merely longer.) This is a problem because I spend a lot of time looking at that screen: reading e-mail and e-books, checking the news, reviewing apps, and so on. It's to the point where I have to hold the phone at arm's length just to be able to focus on text. (Yeah, I'm overdue for new glasses. But anyone in my age bracket or above understands what I'm talking about.) Increasing the font size gets you only so far.

This point was driven home recently when I spent some time with a Samsung Galaxy S4 (on loan from Verizon), which has a breathtaking 5-inch screen. The jump to there from 3.5 inches may not seem like much, but it's actually an increase of nearly 43 percent. Side by side with the 4S, the S4 dwarfs it. More importantly, it's just so much easier on the eyes.

Of course there are countless other Android-powered models with displays that are nearly as large, just as large, or even larger. But although rumor has it that Apple is tinkering with larger iPhone screens, I suspect the product we'll meet next month will have the same 4-inch Retina Display. Lovely, yes, but still not enough for me.

I'm sure Apple will catch up with the competition eventually, sizewise, but I'm tired of waiting. This customer wants the option of a much larger screen, and unless I get it next month, I'm going to see what the Android life is like.

Anybody else feeling the same impatience for a bigger iPhone? Was the iPhone 5 enough to satisfy your size demands? Or perhaps you feel that OS trumps hardware, and the iPhone still rules? Whatever your thoughts, share them in the comments!