Shares of Apple have struggled to sustain gains since Cook was named CEO, down 3 percent since August 2011, and 25 percent over the past 12 months. Sculley, however, said he has not sold any stock in the company.
"I haven't sold any stock in Apple. I'm still very optimistic that Apple's going to do just fine. It doesn't mean that Android won't be larger in market share, it already is, but Apple makes great quality products," he said.
'Firing' Steve Jobs
While Sculley has become known as the CEO that fired Steve Jobs in 1985, he denies that claim.
(Read more: How Apple has changed since Steve Jobs)
"I never was the person who fired Steve Jobs, that was a myth," he said.
Sculley did not expand on this, but in a past interview with computer historian David Greelish he said that Jobs was demoted from the role of leading the Macintosh division and then went on sabbatical and eventually resigned from the company.
Can BlackBerry be rescued?
Discussing his views on BlackBerry, Sculley said he is "absolutely convinced" the embattled smartphone maker can be turned around.
"The challenge is you can't sell a phone for $700 in most of the world, so there has to be some real rationalization on the device side of the business," he said.
"If you can strategically separate the device side of the business, it can be under the same ownership, but operationally separate from the enterprise service business, there's a terrific chance to turn BlackBerry around," he added.
(Read more: BlackBerry gets bids, and Apple gets cleared)
In late-September, BlackBerry agreed in principle to be acquired by Fairfax Financial, a Canadian insurance company, for $9 a share in a deal worth $4.7 billion. The company is currently in a six-week shop period where it can solicit, receive and enter into negotiations with other interested parties.
Cisco, Google and SAP have expressed interest in pieces of BlackBerry, according to a report by Reuters. Any such transaction would be separate from the deal struck with Fairfax Financial to take the company private.
"It needs a strategic investor. But as you know in the tech world, if you don't do things quickly, if you just come in and think you can strip it for parts, or let it take care of itself, it won't happen," he said.
—By CNBC's Ansuya Harjani; Follow her on Twitter