GLOBAL MARKETS-Apple weighs on stocks, while oil prices steady

(Updates prices, changes comment, byline, dateline) * Brent oil stabilizes above $50 a barrel after 5 pct drop * U.S. dollar hits 3-1/2 month high against Swiss franc * Stocks little changed globally; China up, Europe off By Rodrigo Campos NEW YORK, Aug 4 (Reuters) - Apple weighed heavily on all major U.S. stock indexes on Tuesday as it fell for the fifth straight day, while oil steadied a day after a broad measure of commodity prices hit a 12-year low. Apple stock, d