Apple has made some moves recently that could point to more affordable, higher capacity iPhones. First, they dropped the price delta for doubling the storage of iPod touch models. Before the move, customers had to pay $100 to go from 16GB to 32GB or from 32GB to 64GB. Now, that price difference is $50. This change was appreciated, but overdue. Considering that storage capacity prices have dropped since 2007, when the iPhone was first introduced, that $100 surcharge was out of date.
Additionally, Android users can usually add storage capacity using low-cost microSD cards. Apple isn't likely to offer expandable storage, as they've gone in the opposite direction. MacBook Airs and even newer MacBook Pros cannot expand their memory.
Speaking of the MacBook Pro, Apple also made 16GB the base configuration for the 15-inch model. I recently traded in my 8GB MacBook Pro with Retina display, using SellYourMac.com, and purchased a 16GB MacBook Pro with Retina display. If that original model had been expandable, I could have added low-cost memory, possibly from a third party.
These changes show Apple is being more sensible about storage capacity requirements and pricing. Is it possible the iPhone 6 will have $50 price tiers, for doubling the storage capability, with basic models starting at 32GB and going all the way up to 128GB?
