This year’s Black Friday sales were 26 percent higher than last year, according to Comscore. This is a good sign for the US economy and job market. Stores like Amazon, Walmart, Best Buy, Target and Apple all saw banner sales days. What was most interesting was the use of mobile apps and social networking in the promotion of Black Friday and cyber Monday deals. Mobile device purchases rose to 9.8 percent of online sales, up from 3.2 percent last year.