It said the sales cycle was almost the same as the iPhone 6 series, the model that helped Apple achieve what it described as the Cupertino company's "first volume super-cycle at the cusp of 4G transition".
The latest super-cycle came after six generations of iPhones and on the cusp of the transition to 5G.
Counterpoint said the iPhone 6 sales had been driven by pent-up demand for models with a larger screen, while in the case of the iPhone 12 series, the attraction was 5G and a full OLED screen.
The research company also said there had been a change in model preferences between the iPhone 11 and 12, with consumers preferring the most expensive version of the iPhone 12 during the seven months it took to reach 100 million in sales.
"The share of the Pro Max version in the iPhone 12 series sales was 29%, compared to 25% for the same model of the iPhone 11 series," Mishra said. "This is also one of the reasons for the iPhone 12 series grossing 22% more revenue than the iPhone 11 series in the first seven months since its launch."
He pointed out that the base variants of the iPhone 11 Pro Max and the iPhone 12 Pro Max cost the same: US$1099 (A$1461). The differences were that the 12 Pro Max had 5G capability, more RAM, and the A14 Bionic chip. Additionally, a charger and headphones were not supplied.
"However, this did not seem to be a deal-breaker for consumers, especially in the US, which contributed to 40% of the global iPhone 12 Pro Max sales till April," Mishra said.
"The upgrades, which came at the same price as that of the iPhone 11 Pro Max, supported by aggressive operator promotions, helped the 12 Pro Max sales soar to make it the highest-selling device in the US consistently since December 2020.
"Moreover, the iPhone 12 series was also comparatively less affected by the pandemic than the iPhone 11 series. Consumers who held on to their devices last year due to the pandemic, upgraded to the 12 series."
Mishra said Apple had achieved a record-high market share for April and it had done so since October 2020, with the trend likely to continue in May 2021.