Microsoft Corp named wireless industry pioneer John Stanton to its board on Wednesday, adding a director with experience in the mobile sector it has struggled to crack. The move to appoint Stanton, 58, who until last year was the chairman of wireless broadband company Clearwire Corp, comes six months into the leadership of new Microsoft CEO Satya Nadella, whose motto for the company is mobile-first, cloud-first, veering away from its historical strength in PC software. Investors have applauded Nadellas forward-looking stance, but still have concerns about the $7.2 billion purchase this year of Nokias handset business, which thrust Microsoft directly into the phone market, but has yet to deliver results with only about 4 percent of smartphones globally running Windows software. Two weeks ago, Nadella announced 18,000 job cuts at Microsoft, with most coming from the phone business it acquired from Nokia.