If portability is the key, and if you already own a tablet or use a traditional computer for everyday tasks, the iPhone 6 should do nicely. Of course, smaller is relative; even though it's dwarfed by the Plus, the iPhone 6 screen is still 38% larger than the iPhone 5.
Personally, I've decided on the iPhone 6 in Space Gray with 128GB of storage; storage is more important to me than screen size and resolution — especially considering the pixel density of the Retina HD displays. Sure, the Plus may pack a million more pixels into the display, but there comes a point of diminishing returns, and since I'm on the go a lot, 4.7-in. model will be more pocket-friendly for hikes and trips.
After putting it off for a few years, Apple engineers have finally embraced the larger-sized screen found on competing phones. But instead of slapping on a big screen and calling it a day, Apple also optimized the software to take advantage of the larger screen real estate. Even though there are inherent tradeoffs between models, either iPhone 6 will still have access to the standout iTunes app and media ecosystem.
If you're a fan of the iPhone, neither choice will leave you disappointed. In fact, I expect the larger screen sizes will lure new customers into Apple's fold.
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