Last summer, Apple's (NASDAQ:AAPL) lead in the smartphone market, measured by the company's share of industry profits, was far beyond second-place Samsung. But since then, Apple's share of smartphone profits has leaped even further, highlighting the tech giant's dominance in the massive market.

Iphone

iPhone 6. Source: Apple.

Apple's soaring iPhone business
The last 12 months have been great for Apple. Not only has the stock been up 31% during this time, trumping the S&P 500's gain of 6.5%, but Apple's underlying business also has been firing on all cylinders, particularly its phone business. In its most recent quarter, for instance, it sold 61.2 million iPhones, up from 43.7 million in the year-ago quarter. Even more, the average selling price of iPhones during this time actually increased, rising from $596 to $659.

Furthermore, of the world's eight largest smartphone makers, Apple captured 92% of operating profits in Q1, according to data compiled by Canaccord Genuity (via The Wall Street Journal). Canaccord data, which includes losses in its calculations for coming up with total operating profits for the eight smartphone makers, pegged Samsung's share of operating profits at 15%.

Perhaps even more impressive than Apple's large share of profits, however, is the leap in share from the year-ago quarter -- a year ago, Apple's share of operating profits was at 65% and Samsung's was at 35%. As the statistics suggest, Apple's rising share of smartphone profits has, indeed, negatively affected Samsung. Apple CEO Tim Cook has noted on several occasions that the latest line of iPhones has sparked an unusually high proportion of smartphone users switching from Android smartphones to iPhones. And given Samsung's dominance of high-end Android devices, along with the company's declining share of high-end smartphone sales in the past 12 months, a meaningful portion of these Android switchers are certainly coming from Samsung's flagship Galaxy smartphone line.

But most striking of all is Apple's share of operating profits relative to the company's share of smartphone unit sales. In the same quarter, Apple captured 92% of the top eight smartphone maker's operating profits, the Cupertino-based company's share of these companies' unit sales was just 20%, Canaccord reports.

Samsung's recent struggle to compete with Apple isn't new. Samsung's challenges really began to stand out in Q4, when its operating profits declined 36% year over year, driven primarily by its plummeting profits in its mobile division, which fell 64.2% year over year.

Iphone

Source: Apple.

Tough times for Apple competition
Apple's success has made achieving operating profits in the iPhone-dominated market difficult. Samsung isn't the only smartphone maker struggling to compete with it.

Last week, Microsoft announced in a press release that it would cut 7,800 jobs -- most of which are related to its phone business. Along with the layoffs, Microsoft essentially dubbed its acquisition of Nokia, which occurred just last year, a failure; the company wrote off $7.6 billion "related to the assets associated with the acquisition of the Nokia Devices and Services (NDS) business" -- about $400 million more than price Microsoft paid to acquire the company. While Microsoft CEO Satya Nadella said the company would still bring phones to market, it will be a more focused portfolio of devices.

Smartphone makers BlackBerry and Lenovo, two of the world's largest smartphone makers, also continue to struggle. Measured by operating profits, both operate near breakeven, as measured by operating profits, according to Canaccord.

Apple's ability to capture the lion's share of smartphone profits, despite its relatively smaller share of unit sales, illustrates its pricing power and impressive margins -- two key factors in the bull case for Apple stock. Apple investors bet the company's history of pricing power and uncanny margins in its smartphone business are evidence that the tech giant has an enduring competitive advantage over its peers.

Daniel Sparks owns shares of Apple. The Motley Fool recommends Apple. The Motley Fool owns shares of Apple. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.