Shares of Skyworks Solutions (SWKS) were up 13.5% in midday trading Thursday, at a four-month high, after the company's quarterly results reported late Wednesday handily beat estimates and it raised its guidance. Skyworks makes analog chips used in Apple (AAPL), Samsung and other smartphones. For its fiscal Q1 ended Dec. 28, the company reported revenue of $453.7 million, up 15% from the year-earlier quarter and its biggest gain in the past four