Apple Watch. 

Investors reacted with pessimism to Apple's (NASDAQ:AAPL)earnings report for the third quarter of fiscal 2015. Shares of the iPhone maker fell by nearly 5% after the announcement, and the stock is still trading nearly 10% below its highs of the last year. However, not everything is what it seems, and short-term price movements don't necessarily make much sense from a long-term point of view. 

The main numbers
Those looking for an explanation for Apple's decline after earnings won't find it in the main sales and profit figures, since it reported both revenue and earnings per share above Wall Street forecasts. Total sales grew 33% to $49.6 billion during the quarter; the number was above the $49.3 billion predicted on average by analysts following the company.

Gross profit margin came in at 39.7%, above the average forecast of 39.5% among analysts polled by FactSet, and also better than the company's guidance for 38.5%-39.5%. Apple reported $1.85 in earnings per share during the last quarter, a big increase of 45% year over year, and surpassing expectations for $1.81 per share.

Some analysts may have felt disappointed with forward-sales guidance; Apple expects revenue during the September quarter to be between $49 billion and $51 billion. Wall Street analysts are on average forecasting $50.85 billion, so Apple will need to report near the high end of its guidance in order to beat estimations.

Still, this is hardly much of a reason for concern, since Apple has delivered sales above its guidance range over the last several quarters. As a reference, the company expected revenue to be between $46 billion and $48 billion for the June quarter, a range it overperformed with $49.3 billion. Apple is a widely followed company, and it makes sense to assume that analysts are keeping this trend in mind and putting the numbers in perspective when analyzing the company's sales guidance.

The weakest spot in the report was arguably iPhone unit sales. Apple sold 47.5 million devices during the quarter, a 35% increase over the same period last year. Wall Street analysts, on average, expected 49 million units, so the number was below expectations.

Prices were remarkably strong, though. The average selling price in the iPhone segment was $660, a new record for Apple. In terms of revenue, iPhone sales grew by an impressive 59% annually to $31.4 billion.

Who missed what?
iPhone sales were below analysts' forecasts, since the product brings in more than 60% of Apple's revenues, this can be seen as a reason for negativity. However, it's important to note that Apple's competitive position in smartphones has never been stronger, and the new iPhone 6 and iPhone 6 Plus models are showing impressive momentum. According to CEO Tim Cook during Apple's earnings conference call:

The strong iPhone results were broad-based in both developed and emerging markets and we experienced the highest switcher rate from Android that we've ever measured. 

Stock prices are driven by company fundamentals in the long term, but perceptions and investor sentiment can be remarkably powerful on a short-term basis. When someone says that Apple missed sales expectations on its much important iPhone segment, this can sound like a valid reason for concern.

However, that's not the right way to say it. Apple is in the business of selling tech products and services, while analysts are in charge of estimating how many devices the company will sell over a specific period of time. Wall Street analysts overestimated iPhone unit sales; the company did not miss its own guidance.

Actually, Apple does not provide any kind of guidance on iPhone unit sales. It gave investors an estimated range for total sales and gross margin, and it exceeded the high end of both ranges during the last quarter.

The iPhone is doing better than fine. Apple reported broadly solid sales and earnings figures, and its growth rates are nothing short of amazing for such a massive corporation. If anything, the short-term decline in Apple stock after earnings looks more like a buying opportunity than a cause for concern.