New developments

In a Facebook post today, Zuckerberg said it will ban developers who don't agree to an audit. An app's developer will no longer have access to data from people who haven't used that app in three months.

Data will also be generally limited to user names, profile photos and email, unless the develop signs a contract with Facebook and gets user approval.

What actually happened?

Earlier in yesterday, an academic who developed the app used by Cambridge Analytica to harvest data said that he had no idea his work would be used in Donald Trump's 2016 presidential campaign.

Alexandr Kogan, a psychology researcher at Cambridge University, told the BBC that both Facebook and Cambridge Analytica have tried to place the blame on him for violating the social media platform's terms of service, even though Cambridge Analytica ensured him that everything he did was legal.

"My view is that I'm being basically used as a scapegoat by both Facebook and Cambridge Analytica," he said. "Honestly, we thought we were acting perfectly appropriately, we thought we were doing something that was really normal."

Facebook share prices drop

Authorities in Britain and the United States are investigating the alleged improper use of Facebook data by Cambridge Analytica, a UK-based political research firm.

Facebook shares have dropped some 9 percent, lopping more than USD 50 billion off the company's market value, since the revelations were first published, raising questions about whether social media sites are violating users' privacy.

Cambridge Analytica CEO Suspended

The head of Cambridge Analytica, Alexander Nix, was suspended yesterday after Britain's Channel 4 News broadcast hidden camera footage of him suggesting the company could use young women to catch opposition politicians in compromising positions.

Footage also showed Nix bragging about the firm's pivotal role in the Trump campaign. Nix said Cambridge Analytica handled "all the data, all the analytics, all the targeting" for the Trump campaign, and used emails with a "self-destruct timer" to make the firm's role more difficult to trace.

"There's no evidence, there's no paper trail, there's nothing," he said. In a statement, Cambridge Analytica's board said Nix's comments "do not represent the values or operations of the firm, and his suspension reflects the seriousness with which we view this violation." Facebook itself is drawing criticism from politicians on both sides of the Atlantic for its alleged failure to protect users' privacy.