June 29 (Reuters) - Twitter Inc (TWTR.N) on Tuesday named Sarah Personette as chief customer officer to oversee the social media platform"s global ad sales, global content partnerships and revenue operations. Personette, who is vice president of global client solutions, will step into her new role on Aug. 1. She will replace Customers Lead Matt Derella, who will leave after nine years at Twitter. Personette"s appointment comes as Twitter aims to double annual revenue by 2023, and expand its advertising capabilities to better compete with digital ad giants including Facebook Inc (FB.O). Personette leads Twitter"s relationships with top marketers and ad agencies. She will report directly to Chief Executive Jack Dorsey and oversee Twitter"s "emerging businesses," including MoPub, an advertising technology product that helps app developers and mobile publishers earn ad revenue, the company said.