Mobile is one of the most closely followed spaces in all of investing at the moment, as the opportunity here in this relatively nascent and extremely high-growth area is almost unsurpassed. Many investors have seen Apple (NASDAQ: AAPL) shares slipping recently and have been wondering whether the company will be able to hold its impressive smartphone and tablet market shares, as the competition is now beginning to get very fierce from all sides. In this video, Motley Fool tech and telecom analyst Andrew Tonner tells us why Goldman Sachs is very bullish on Apple going forward in the mobile market. The reason might surprise you.