Last quarter, Apple sold almost 75 million iPhones worth more than $51 billion. That’s a staggering amount, and the smartphone accounted for nearly 70% of Apple’s total revenue. The company “only” sold 21.4 million iPads worth just under $9 billion, or around 12% of Apple’s quarterly revenue last quarter.

That’s down from $11.5 billion and 26 million iPads in the quarter a year ago, and it’s led some analysts to wonder if the age of the iPad is over — if the smartphone and the PC are again squeezing out the device that Steve Jobs said fit in between those two categories.

Don’t tell Tim Cook that, though. In Apple’s quarterly earnings conference call with analysts, he laid out a forceful declaration that the iPad has a long, fruitful life ahead of it.

While acknowledging that sales had dipped in the short term, in “90-day clips” as he called it, Cook said he was “very optimistic and bullish on iPad over the long run”, according to a transcript of the call from Seeking Alpha.

He cited customer satisfaction ratings on the iPad that sometimes touch 100%, something “unheard of” according to Cook. He said that in developed markets like the US, UK, and Japan, half of all iPad buyers are doing so for the first time. And in China, that number is more than 70%. Definitely not a saturated market, and plenty of room for growth.

But aside from the consumer markets, which are huge to be sure, Cook was especially excited about the partnership with IBM that was launched last year.

“I think we’re really going to change the way people work,” said Cook. “I’m really excited about the apps that are coming out and how fast the partnership is getting up and running.”

Earlier in the call, Cook said that IBM will release an additional 12 MobileFirst apps this quarter, to go with the 10 apps that were launched back in December. Three of those will come in new industries, healthcare, energy and utilities, and industrial products. That will bring the total number of apps to 22, and Cook said the two companies are on track to have more than 100 specific enterprise apps by the end of 2015.

These apps are important. As Cook noted, the iPad is more than productivity apps like Microsoft Word or Excel. It is perhaps at its most powerful when there are industry-specific apps that solve a particular problem or help employees work in a different way.

“That’s one of the things that working with IBM provides us,” said Cook. “They bring a significant amount of knowledge on all of the verticals… I think if we can really change the way people work… the opportunity is enormous.”

Cook notes that Apple’s iPad penetration across Fortune 500 companies is nearly universal, but that penetration is broad but not deep. There are a small number of employees at each company using iPads, because it may not always make sense for their job. A line technician for a power company might not use Word or Excel nearly as much as an office worker.

But if you can build a custom app for that line technician that’s designed around his needs and workflow, that can make him more valuable as an employee and encourage companies to roll out iPads to more of their workforce.

That’s why Tim Cook is excited, and that’s why the IBM partnership is so important — to help industries create apps and streamline processes — and, of course, sell more iPads.

What vision does your company have for the iPad? Let us know in the comments below.