Apple is no longer the world's leader in innovation, Aspen Institute CEO Walter Isaacson told CNBC on Tuesday.

Instead, companies like Google and Amazon are the new leaders, the biographer of Steve Jobs said.

"Apple is no longer the most innovative of companies," Isaacson said on CNBC's "Squawk Alley." "But they are good at execution."

The innovation in the virtual assistant space, for example, is coming from Google and Amazon, not Apple, Isaacson said.

He's surprised Apple hasn't moved it's virtual assistant Siri into the home. "I use both Amazon Alexa, and Google Home. ... Sometimes I let them compete," said Isaacson. The value of the virtual assistant model isn't just the hardware, but the potential for an ecosystem of apps, he said.

Apple will likely release a home assistant device soon — possibly this summer — but Isaacson thinks it could be too late for the company to catch up in that space. Instead, Apple should look at other areas that are ripe for innovation.

"You could have a great company — and Apple is a great company — without having really a next big thing, but it isn't in Apple's DNA to be that way," said Isaacson.