Apple reported $65.8 billion in revenue for iPhones in the holiday quarter, down 8 per cent (year-over-year).
However, on a constant currency basis, iPhone revenue was roughly flat, according to the company.
Apple faced supply chain disruptions in October and November as China faced Covid surge and protests erupted at its key supplier Foxconn's main factory in the country.
Cook said that Covid-related challenges "significantly impacted the supply of iPhone 14 Pro and iPhone 14 Pro Max and lasted through most of December".
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"Because of these constraints, we had significantly less iPhone 14 Pro and iPhone 14 Pro Max supply than we planned, causing ship times to extend far beyond what we had anticipated," he noted.
Cook said that as a result of a challenging environment, "our revenue was down 5 per cent year over year".
"But I'm proud of the way we have navigated circumstances, seen and unforeseen, over the past several years, and I remain incredibly confident in our team and our mission and in the work we do every day," he said in an earnings call with analysts.
"Our customers continue to rave about the astounding camera capabilities and unprecedented battery life and the groundbreaking suite of health and safety features. The iPhone 14 lineup pushes the limits of what users can do with a smartphone," he added.
During the quarter, Mac revenue came in at $7.7 billion, which was in line with what Apple had expected.
During the quarter, iPad revenue grew 30 per cent to a total of $9.4 billion.
