Apple reported iPhone revenue of $56 billion for its fiscal first quarter on Tuesday, blowing past analysts' estimates, proving that the new iPhone 11 is off to a strong start.

IPhone revenue for the quarter rose 8% from a year earlier and climbed from the fourth quarter when Apple generated $33.36 billion in iPhone sales. Analysts were expecting revenue for the devices to come in at $51.62 billion in the first quarter.

The big bump was partly because this was the first full period to factor in sales of the iPhone 11, which launched last year. CEO Tim Cook said in Tuesday's earnings release that the company saw "strong demand for our iPhone 11 and iPhone 11 Pro models."

"People love the battery life. They love the camera. They love the industrial design. The battery lasts all day," Cook told CNBC's Josh Lipton Tuesday, referring to the iPhone 11. "We also hit the right price with it."

The fiscal first quarter also covers the important holiday season, which leads to a bigger revenue lift compared to other parts of the year.

Apple has gradually turned its focus toward other areas of its business like wearables and services, amid broader stagnation in the smartphone market. The company hinted at the move when it stopped breaking out iPhone unit sales last year.

The iPhone is still Apple's most important product, claiming a significant share of its overall revenue. There's growing speculation that Apple could launch its first 5G phone in September, which could reignite slumping iPhone sales and drive a renewed "supercycle" for its stock. However, analysts say Apple may not be in a rush to release a 5G phone, since the fastest 5G networks aren't widely available yet.

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