With Apple's earnings coming after Monday's closing bell, analyst Chris Caso said key wildcards are the mix of iPhone 6 and iPhone 6 Plus sales and whether the company successfully enticed a large number of consumers to buy devices with larger memory.
The Susquehanna Financial Group senior analyst estimates that 57 million iPhones were sold in the quarter ended in March, a bit higher than the consensus forecast, with "more 6 Plus and more of the higher memory" devices than many had predicted.
With the introduction of iPhone 6, Apple dropped the 32GB offering. "So basically for another $100 you can go right from 16 gig to 64 gig," Caso told CNBC's "Squawk Box" in an interview. "That's been very profitable for them." Apple still offers the iPhone 5s in 32GB.
Apple is expected to report earnings of $2.16 per share on revenue of $56.1 billion for its fiscal second quarter, according to analyst forecasts.
"Apple is really going to need to kind of blow the number out, given their recent success in prior quarters," S&P Capital IQ analyst Angelo Zino told CNBC. He expects a good quarter on the back of iPhone sales, and any strong dollar impact should be already factored in.
Caso said he'll also be watching for how much cash Apple returns to shareholders. "Over the last year, they returned about 90 percent of what they generated. And I think there's a good chance they'll return more than that this year," he said.
"We believe the bogey for investors is a 15 percent increase to Apple's total reported capital return number (shares repurchase plus past dividends), which would imply a $150 billion headline number, up from $130 billion announced last year," Piper Jaffray analyst Gene Munster said in a recent note.
Apple has $178 billion cash on hand, according to the tech giant's quarterly results in January, which saw the company make $3.06 per share on $74.6 billion—both had far exceeded expectations.
As for the stock, Caso has a buy rating on Apple, with a $150 per share price target in the next 12 months. Shares closed Friday at $130 and change.
"When you go into the June quarter, now that's usually the lull quarter between iPhone launches. That will be down," he said. "But that's the quarter when you get the Apple Watch [results]. That kind of bridges the gap."
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The Apple Watch went on presale April 10 and launched this past Friday.
"We have about $3.5 billion of Apple Watch revenue into next quarter," Caso said—adding watch sales don't figure too much in his calculations for Apple's future stock price.