Apple has now sold over two billion iPhone units
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When Apple sold its billionth iPhone in July 2016, it was cause for celebration in Cupertino. At the end of our article noting the event, yours truly wrote "With all of the changes made from the first iPhone sold to the billionth, we wonder what changes will be made to the phone by the time Apple celebrates the two billionth handset sold." Well, we can wonder no more.
Apple has sold over two billion iPhone units
With more than one billion active iPhone users, those using Apple's iOS-powered handset make up 26% of all global smartphone users. In the U.S., that figure is closer to 60% and is near 50% in the U.K. These numbers are at or near all-time highs, and the percentage of survey respondents who switched over to an iPhone over the last two years in the U.S. and the U.K. weigh in at 14% and 10% respectively.

The number of iPhone variants released each year are now up to as many as four
Deidu says that Apple still follows the philosophy of its late co-founder and CEO Steve Jobs who believed that Apple should deliver products and features that consumers didn't know that they needed. As the analyst says, "We did not ask for rack focus, post-production focus (!), night mode, macro photography and portrait bokeh. But once we have these features we begin, ever so slowly, to use them and then we start demanding them."
Analyst says that the iPhone 13 line is Apple's most important yet
He also points out an interesting stat that we first heard from Gene Munster of Loup Ventures. There are 400 million iPhone users currently using an iPhone that is three years of age and older. That provides Apple with a large number of potential upgrade candidates. And with carriers offering extremely high financial incentives to trade-in their older models (up to $1,000 depending on the wireless provider), we could see some of those 400 million make the move to a brand spanking new iPhone.
Deidu says that the iPhone 13 series is the most important one yet. He explains how that he reached this conclusion: "It creates the perception of what a phone should be and it sets up the trajectory for demand that did not yet exist. It’s facile to think that the utility of an ok older phone is good enough. That assumes that we are satisfied with ok messaging and ok apps. With ok photos and ok video. With no wide angles, no night mode and no macro photos. What the iPhone has shown however is that the demand for performance can be nudged up."
Things that are NOT allowed: