The reason why the iPhone is so popular is because of its ease of use and of course the brand. People don’t really care that the S4 has 8 cores, they just want something that has a slick, smooth OS which isn’t laggy and that can show them what they want to see and allow them to do what they want to do. I’m not saying the S4 is this but you know, I can’t really see the difference between 400ppi and 350 (maybe cuz I wear glasses but hey).
The iPhone has a good design and many consumers just want something that looks good, maybe not as much about the functionality. They also care about that Apple logo on the back. Apple has always marketed themselves as a niche, creative company (though they may have slipped slightly, they are still this), and people want that. Why do people buy £100 scarves from Louis Vuitton? Because they have that ‘LV’ logo on them.
I bought my iPhone because it was the best in its class when it was being made. It looked good and had a fast processor. It has lasted me from purchase about 3 years and I think that is amazing for it to still run the latest OS. A Samsung Galaxy S doesn’t even run Android 4.0 and it was released the same year as the iPhone 4 (2010).
As shown by the constant decline in the amount of ‘point and shoot’ cameras, people love to take pictures on their iPhones and Smartphones and the availability of a good camera at the time of the 4’s launch was unprecedented for its time.
The iPhone was the first real ‘smartphone’, introducing the capacitive touchscreen for nearly every smartphone to come. It also introduced high PPI displays on a phone. It also introduced 3rd party Apps on a store which people could access on their phone with ease in July 2008 whilst Android followed in October (available to the public). Apple was the start of all this. Maybe they aren’t in front any more but you have to give credit that they really did change what we think of now as a phone.