Oh how quickly things can change. One year ago, shareholders were wondering whether Google could ever adapt to a world fueled by mobile. Now,  Google's mobile advertising is the chassis that carries  Alphabet and all of its umbrella businesses.

"The strength of the quarter is about mobile," said Google CEO Sundar Pichai, speaking during the latest  earnings call for Alphabet, the search giant's parent company. "It's transformed the way that people consume information, and Google's products have become a central and much loved part of their experience."

The company's stock price enjoyed a 4 percent bump in after-hours trading after Alphabet managed to beat analysts' estimates on earnings per share and revenue, which came in at $21.5 billion for the quarter, up 21.3 percent from the same period in 2015.

"The fact that Google knows how to deliver great content and offer an attractive return on investments for their advertisers means that they have a very bright future," said Shawn McMurray, portfolio manager at McMurray Alpha Capital.

As recently as early 2015, Google was struggling to turn around its slowing advertising business as the company wrestled with a changing world in which consumers use their phones, not their laptops, for the bulk of their searches. Mobile was Google's Achilles heel, but that vulnerability is now a thing of the past.

"Mobile could have led to business model or competitive disruption, but Google appears to have transitioned successfully and remains the preferred search engine for mobile users, perhaps helped by ubiquity of Android," said Jonathan Opdyke, CEO and Co-founder of HookLogic, a performance marketing company.

Aside from mobile, Pichai also spent portions of the call praising other portions of Google's business. In particular, Pichai made it a point to highlight Google's efforts in artificial intelligence and machine learning, which he said will be the big driver of the company's future and is already beginning to benefit users today.

"The big story that is starting to emerge especially this quarter is how mobile is the driving force of advertising revenue today while machine learning will be the driver into the future," said Johnny Won, founder of Hyperstop, a tech consulting firm.

Alphabets "Other Bets," which include the company's long-term efforts in self-driving cars, delivery drones, smart cities and so on, saw increases in revenue but much broader increases in operating costs. Based on the stock's after-hours activity, most analysts and investors remain patient with Alphabet's efforts to find its next Google, but some are beginning to grow antsy.

"It's OK if some of them don't make money--even if most of them don't make money--but none of them contributing to the bottom line has to make investors think Google is pissing its money away in a futile attempt to diversify away from being a 90 percent search advertising company on a revenue basis," said Phil Davis, CEO of Phil's Stock World Investments. "See Yahoo for what becomes of that over time."