NEW YORK, April 24 (Reuters) - U.S. stocks ended mostly higher in a choppy session on Thursday, powered by a rally in Apple shares a day after the iPad maker's strong results, though tensions in Ukraine limited gains.
Based on the latest available data, the Dow Jones industrial average was unchanged to end unofficially at 16,501.65. The S&P 500 gained 3.22 points or 0.17 percent, to 1,878.61. The Nasdaq Composite added 21.372 points or 0.52 percent, to close at 4,148.338.
Reporting by Caroline Valetkevitch; Editing by Jan Paschal