Apple (NASDAQ:AAPL) shares had a great run leading up to the stock split, and investors are very happy that the company is near its all-time high. The company's stock price is still reasonably cheap and can move past its previous high, but Apple will find it very hard to see high revenue growth in the future. With already huge revenue and high iPhone penetration rates, Apple might have a hard time growing in the future unless it comes out with blockbuster products. 

New products
Apple unveiled new operating systems at the 2014 WWDC conference, but investors have expressed disappointment because the announcements all had to do with software upgrades and weren't really material drivers of Apple's fortunes. The company launched iOS 8 with new features and platforms like HealthKit and HomeKit, and it is a good upgrade. Apple also came out with Yosemite OS for Mac users. 

However, the company has stated that it has a large pipeline of products coming out in the back half of 2014. In recent years, the innovation engine of Apple has definitely slowed down and the company has resorted to product refreshes -- most of which are largely evolutionary and not revolutionary.

The company continues to face massive competition from smartphones running on Google's(NASDAQ:GOOGL)(NASDAQ:GOOG) Android OS, and more OEMs are joining the party, with Amazon just unveiling its Fire Phone. So if Apple's iPhone 6 is not as innovative as many are expecting, the company might see a lower rate of customer adoption, which is a very real possibility considering the number of choices that smartphone buyers have at their disposal.

Law of large numbers
The recent rally in Apple's shares can almost entirely be attributed to the stock split and the increased capital returns program of the company. The $44 billion left in Apple's share-repurchase program will aid the company in growing its earnings per share. However, if Apple fails to launch a major product, the company's EPS might take a hit. 

There's a lot of pent-up excitement for the iPhone 6 among Apple fans, but the product refresh might be a disappointment. There have been numerous suggestions and speculations in the media that the iPhone 6 will have a large screen size -- ranging anywhere between 4.7 inches to 5.5 inches. However, Samsung has had large-screen phones for a long time.

According to IDC, Samsung had a 30.2% market share of all smartphones shipped in the last quarter, whereas Apple's market share stood at 15.5%. Samsung has utilized Google's open-source Android and has gained widespread consumer acceptance. So a larger-screen iPhone 6 might not be as big a hit as many Apple fans are anticipating, and as the stock price is very close to its all-time high, the stock might take a hit, too. 

Apple is a mature growth company with market capitalization of more than $550 billion, and it is unlikely to be a massive wealth creator. Apple's revenue guidance of $36 billion-$38 billion for the current quarter implies revenue growth rate of 1.9%-7.6%, even though the company is going to have a larger presence in China in this quarter.  The large revenue of Apple will make it harder for the company to grow, as it will be a victim of the law of large numbers. Also, Apple saw revenue from iPad sales decline 13%, year over year, to $7.6 billion. The company cited changes in channel inventory for the decline, but it just might be a sign of declining growth. 

Valuation still reasonable
The stock had a huge run, but the valuation still seems reasonable. However, Apple still faces extensive competition from Google, Samsung, Amazon, etc. Apple trades at 13.4 times its estimated fiscal 2015 earnings per share of $6.88. And that EPS number might receive a boost from the company's share-buyback program. However, the company's innovation and product cycle still has to deliver big before Apple can see healthy double-digit revenue growth again.