Has Apple grown overly dependent on the iPhone? Two-thirds of Apple sales seen coming from phone Getty Images Apple makes almost 70% of its money from those little white boxes With Apple Inc. logging yet another record quarter for iPhone sales on Tuesday, one analyst is cautioning against what he considers the company’s overreliance on the device that pioneered the smartphone market. Apple AAPL, +6.47% said it sold 74.4 million iPhones in the December quarter, better than the 68 million predicted on Wall Street, according to FactSet. The record demand translated to $51.2 billion in iPhone sales, comprising 69% of Apple’s overall first-quarter revenue of $74.6 billion. Apple CEO Tim Cook said iPhone demand has been “staggering.” However, it also makes Apple “tremendously dependent” on the iPhone, said BGC Partners analyst Colin Gillis. That may become a problem down the road as growth of the overall smartphone market continues to decelerate, he said. While smartphone unit growth averaged above 40% in 2012, it peaked at 52% in June 2013. The market has since decelerated, with data giant IDC reporting world-wide smartphone shipment growth of 25% in the third quarter. BGC expects the smartphone growth rate to eventually slow to the level of the broader mobile phone market, which currently expands in the 5% to 10% range. Pacific Crest analyst Andy Hargreaves said fewer upgrades during the next iPhone cycle -- given such strong upgrade rates in December -- may prevent “meaningful EPS growth” in fiscal 2016. Things, of course, look much sunnier for Apple in the short term. Hargreaves said “extraordinary current demand” will likely drive fiscal 2015 estimates even higher. Apple has recently started to diversify, introducing its first wearable, Apple Watch, at the end of 2014, and launching a mobile payments platform, Apple Pay, in partnership with top U.S. banks and 200,000 retail locations. BGC projects Apple will sell 30 million Apple Watch units in the first four quarters after its debut, which would compare with 19.4 million iPads sold and 11.6 million iPhones following their respective launches--that is an optimistic projection given hardware in recent quarters has contributed more than 85% to Apple’s overall revenue (mostly due to the iPhone). Shares of Apple fell 2% to $110.82 on Tuesday before the earnings report, but rallied 5% in after-hours trade . They are up more than 40% over the past 12 months. Jennifer Booton