Apple (NASDAQ: AAPL) today celebrates 30 years since the first Macintosh was introduced. Apple spent $500 to produce its first Mac and sold it for $2495, setting the precedent for its premium product approach that has since minted billions of dollars for the company. This approach has allowed the company to charter its unprecedented growth trajectory. Today, Apple is more valuable than Microsoft and Amazon combined.

Activist investor Carl Icahn believes that Apple’s growth narrative will stretch out into the future. Icahn, through his company Icahn Capital Management, bought Apple in August 2013 with the intent of swaying the management, CEO Tim Cook in particular, to offer higher buybacks. Although Cook has not yet heeded his call, Icahn is not giving up. As we reported Wednesday, Icahn purchased $500 million more of Apple shares, pushing his investment in the smartphone maker above the $3 billion mark. Again, he called for Cook to give his higher buyback and dividend call more attention. On Thursday Icahn announced via Twitter, spending an additional $500 million on Apple shares.

Bought another $500mil of $AAPL tday, bringing our total to $3.6 billion. If board doesn’t see AAPL’s ‘no brainer’ value we sure do.

— Carl Icahn (@Carl_C_Icahn) January 23, 2014

Apple Has Great Upside

When Icahn first added Apple to his portfolio in August last year, the stock was trading at $468 a share. As of this writing, Apple is trading at around $556 a share. Clearly, Icahn’s investment has paid off as is. However, there is still more upside ahead and Icahn is keen on squeezing out these gains.

Here are Apple’s two triggers for growth going forward

1. Bigger screen iPhone

A recent report on the Wall Street Journal says that a bigger screen iPhone is on the way. Citing people familiar with the matter, the report identifies increased competition as one of the key informants to this decision.

A larger screen iPhone will allow Apple to capture the lucrative Chinese market. Even after Apple inked a deal with China Mobile, analysts were still skeptical about the iPhone, citing its screen size as a possible deal breaker in the Chinese market. China has an undisguised slant toward larger screens.

2. Samsung woes provide leeway

Another possible trigger for Apple’s growth is the fact that Samsung’s phone business is showing slower growth. Profits were flat in the fourth quarter in Samsung’s smartphone and tablet business, despite an uptick in sales. Margins were squeezed in part by the company’s higher spend on marketing over the holiday shopping period. Also, legal costs, brought about by constant fights with Apple, are hurting Samsung’s phone profits.

While one data point can’t be used to write Samsung off, the company’s flat profit growth suggests that it will either have to slash costs or raise prices. Either way, corrective actions could disrupt its sales momentarily, giving Apple’s iPhone a leeway.

Along with this, there is still some upside ahead of Apple and more notably, more zeros to add to Icahn’s bank account balance.

Buyback And Dividend Increase A Stretch

As they say, you can’t have your cake and eat it. Icahn may gain from Apple’s continued share price appreciation, but his call for increased buybacks and dividends may have to wait a little longer. Undoubtedly, Icahn has a huge investment in Apple. However, his current stake isn’t even 1 percent of Apple. The reality is that he doesn’t (as of yet) have the sway to influence Apple’s policies.

Disclosure: Author represents that he has no position in any stocks mentioned in this article at the time this article was submitted.