Why the iPhone 6 will be bigger: Battery life, data performance, fitness apps

I don't put much stock in most of the rumors about the iPhone 6—including the notion that it's going to be called the iPhone 6. There was only one time that accurate details about a coming Apple phone leaked out, and that was back in 2010 when an unlucky Apple engineer forgot an iPhone 4 prototype at a bar. Tsk, tsk.

But one assumption about the coming phone, which may be introduced at a Sept. 9 Apple event, is almost certainly correct. The new phone will be bigger than previous versions. (At the least, it will come in multiple sizes.) Here's why.

1. Five inches is the new four inches

The iPhone's four-inch, 326-pixel-per-inch display is adequate for most smart-phone operations, but it looks rather puny next to the larger, higher-resolution displays on Android and Windows phones. And that's a shame, as any iPad user will tell you, considering all the neat multimedia content available in the Apple/iTunes ecosystem. The company knows this. It's very likely to up the ante to something approaching five inches. And as HTC, LG, Samsung, and other phone makers have proven to consumers and the design elitists at Apple, it is possible to make a 5-inch display that looks good and can be operated with one hand.

2. Size boosts battery life

In our tests, the iPhone has delivered talk times of about 8 hours on a single charge, depending on the phone network. That's OK, but many of the larger Android models clustered near the top of our Ratings can easily double that. The reason? They have bigger batteries. This is old-school chemistry at work—if you want to store more energy, all else being equal, you need a bigger battery. It would be worth it to Apple to supersize the iPhone even if the only reason was to include a beefier power supply.

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3. GPS hangups could be fixed

Consumer Reports engineers have found that, unlike other 4G phones, iPhones running on CDMA cell networks lose their data connections during voice calls. (So do all Sprint Spark phones.) That means that if you're a Sprint or Verizon customer and you're using a typical navigation app to get from A to B,  the directions may fail if a call comes in. What does that have to do with size? We suspect, though we can't be sure, that the iPhone's current cramped design meant Apple had to do triage on some important voice/data hardware. A bigger model would help the company fix the problem.

4. Big = tough

Fitness is going to be a big part of the next iPhone's operating system, iOS 8. The key evidence for that is the new Health app, which will keep track of miles walked, heart rate, glucose levels, and other vitals. According to the rumor mongers (yes, that includes us), this is evidence that Apple will be introducing its own fitness-focused wearable. But the Health app also gives the company an incentive to make the next iPhone slightly thicker, with a water-resistant skin. That would help it keep up with your workouts—and with companies such as Samsung. 

—Mike Gikas