Apple had another amazing holiday quarter.

Here's the thing: the company's last three months of the year usually balloon because it's when consumers buy all sorts of new Apple devices for the Christmas season. Apple posted a record $18 billion in profit last year, and now it's beat that record with $18.4 billion in profit on $75.9 billion in revenue during the last 90 days of 2015. That means it must've sold a tonne of stuff.

Keep in mind Apple released the iPad Pro and began selling the iPhone 6S and iPhone 6S Plus in China during the period, all of which could have been the main reasons of growth. All we know is what Apple tells us in its report. We can see, for instance, that iPhone sales were indeed the primary revenue driver, but it's hard to determine the success of the Apple Watch and new Apple TV.

Financial results from those products - as well as iPods and other accessories - have been crammed into an "other products" category that doesn't offer up too much detail. Still, Apple admitted it sold 74.7 million iPhones, 16.1 million iPads, and 5.3 million Macs before the close of the quarter on 26 December. So, despite the new iPad Pro, iPads sales slumped 25 per cent year-over-year.

iPad sales are still however up 63 per cent from the previous quarter. Another interesting tidbit from the report is that Apple now has an active install base of 1 billion. That's the amount of Apple devices that were regularly engaged with by customers during the quarter.

So, although most everything seems on the up and up, Apple also predicted that the revenue for the second quarter of 2016, which is the first three months of this year, would fall somewhere between $50 and $53 billion.

Apple posted $58 billion during the second quarter of 2015, meaning it expects its first year-over-year revenue decline in 13 years.

Tune into Apple's conference call at 2 pm PST for more from the company.