Idle, speculative prediction regarding iPhone line-up later this year
iPhone 5s is repackaged as iPhone mini — iPhone 5c design with iPhone 5s internals — and moved down to the US$100 price point iPhone 5c currently occupies.
Like how iPhone 5 was discontinued instead of discounted, I do not think Apple wants to sell an intricately designed unibody aluminium iPhone at a discount. Nomenclature of "mini" because the new flagship iPhone will have a bigger screen size.
iPhone 5c moves down to the $0 price point and iPhone 4s is discontinued (or moved further down to replace iPhone 4 in emerging markets).
Having a budget model by using last year’s model as Apple has traditionally done.
New flagship iPhone called iPhone Air with 4.7" screen at the US$200 price point.
Phone looks to be quite thin at around 6mm, deserving of the Air suffix. Moreover, it ties in nicely with the iPad family’s naming convention and also allows for an iPhone Pro to be introduced (with a price that is $100 more expensive) if the 5.5" iPhone comes to fruition.
Developers will have to support mainly two screen resolutions for the 4" and 4.7" displays just like how they currently have to support 3.5" and 4" displays, hence more or less the same amount of fragmentation.