Apple has innovated loyalty more than any other company. When I'm consulting, I tell my clients, "we have to interact with our customers." But that's not what Apple does. Apple allows you to avoid interacting with them or the carriers. Reliability and functionality create a user experience that allows you to buy and use with the minimal amount of support. Now that you can subscribe for an iPhone, pay every month, and get an upgrade once a year, these phones even more like vehicles. We'll pick a carrier like we pick a car dealer, with minimum commitment.
Quartz: Apple's iPhone Upgrade Program, 2015-Sep-11 by Dan Frommer
...the iPhone has already transformed the mobile industry in many ways. That started at launch in 2007, when buying and owning an iPhone was immediately a different experience than any prior mobile device. Apple handled phone activation, media management, and software updates independently through iTunes, and made its built-in “visual voicemail” a feature of the phone app instead of a carrier service that could be sold separately as an add-on fee.
In 2006, carriers were pushing lousy, Windows-powered smartphones branded after themselves—the AT&T 8525 is just one forgettable example. Meanwhile, Apple didn’t even allow operators to put their logos on the back of the iPhone.