You get what you pay for...
By far the most damning evidence will consist of details concerning hardware return rates: Apple's iPhones are the most robust smartphones you can get.
A recent study reveals that a Samsung Galaxy SIII is the most fault-ridden device in the market, followed by the HTC Desire S and Nokia Lumia 610 -- the iPhone 5 doesn't even make the top ten (though the 4 and 4S do).
Samsung is sufficiently aware of how faulty its devices are that its executives are now scrambling to find a way to make its devices more reliable. (This bears with my anecdotal experience, at least two of my friends bought a heavily subsidized Samsung smartphone "because they are cheap," and now complain of patchy reception, performance and call quality in their devices, which seem to demand frequent restarts.)
In the event Apple chooses to become more aggressive in its war with competing manufacuturers, it will be able to prove its devices strengths as reliable, robust and secure smartphones consumers love to use, and for which software and security upgrades are easily available. Not only will Apple be able to make such claims as it introduces its next smartphone, but it will be in possession of ample evidence with which to back them up. With this release the company will consolidate the reputation that the iPhone is the "Rolls-Royce" of smartphones.
When it achieves this it will prove its domination at the high end of the smartphone market, just in time to release a more affordable iPhone variant that brings that reputation into the reach of many more consumers.
I still consider the iPhone 5S as a likely contender for introduction at WWDC in June, shipping (with iOS 7) in July with an iPhone mini set to hit the shops in time for Christmas.
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