User growth is ‘number one concern’ for Twitter

Writing by Katy Barnato; Reporting by Seema Mody
User growth 'number one concern': Twitter exec

Twitter's main focus is boosting user numbers, a senior executive at the microblogging company told CNBC on Wednesday, following its launch of a new app developer service last month.

The number of monthly active users on Twitter grew less than expected in the third quarter, coming in at 284 million, up 13 million on the previous three months. The news disappointed investors and sent Twitter shares plummeting 10 percent.

Wayne Chang, the 31-year-old serial tech entrepreneur who joined Twitter when it acquired Crashlytics in 2013, said Twitter was focused on broadening the appeal of the platform.

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"That's one of the things we are working hard on every day. Growth is our number one concern, so we have teams right now that are just constantly trying to figure out how to make this even easier for users," he told CNBC from a web summit in Dublin, Ireland, the home of Twitter's European headquarters.

Chang became global head of development experience at Twitter after it acquired crash-reporting solution Crashlytics in January 2013, which Chang co-founded.

This October, Twitter launched its new Fabric service, which is aimed at supporting app developers rather than luring users to the microblogging site.

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"Outside of Twitter itself, Fabric is one our top priorities in the company," said Chang.

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"For us, it is really about helping developers through Fabric, and it is not about putting Twitter first, it is about what we can do to help the ecosystem grow, and then we can grow along with it."

Other than Crashlytics and other programs, Chang is best known for his lawsuit against the Winklevoss twins, which was depicted in the "Social Network" movie.

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—Writing by Katy Barnato, reporting by Seema Mody