Zuckerberg and company had made an early bet on a web-based technology called HTML5, which was supposed to work equally well on different mobile platforms and not require a lot of customization work for each one. But it had become clear that HTML5 apps did not perform as well as apps written specifically for each platform.
To optimize the app and grow on mobile, the company decided to spin out different features and make them their own apps. The most well-known of these spin-offs was Messenger, released in August 2011, which let Facebook users chat with one another. During the development of this app, Instagram began to capture the attention of Facebook employees. This included Zuckerberg, who asked his employees for their thoughts on Instagram and what its popularity meant for how users would interact with photos on their phones.Around the same time, as Facebook began gearing up to go public, Zuckerberg networked with fellow entrepreneurs of promising start-ups.
On Friday, April 6, 2012, Twitter made a $500 million acquisition offer for Instagram, and Systrom alerted Zuckerberg to the offer.