Its new record close of 5,056.06 capped a slow, unsteady climb since it touched a 2002 low of 1,114.11, that spanned an economic recession, the rise of biotech and social media and the explosive growth of mobile phones that has helped make Apple Inc (AAPL.O) the most valuable company in the United States. The Nasdaq traded as high as 5,073.091 on Thursday, led by shares of Apple, which has been among the biggest positive influences on the index in recent years.