Today it was announced Instagram has overtaken Twitter to become more popular with US smartphone users. Nearly 35m Americans used Instagram at least once a month last year, compared with 30.8m using Twitter’s mobile app, according to estimates from E-Marketer, the research group. In another blow to Twitter’s pride, Statista have unveiled this chart that shows businesses don’t believe Twitter can be used directly for sales. After its first earnings announcement last month, Twitter shares fell almost 20 per cent as analysts quizzed the management about whether growth could ever accelerate in the US.