This week in social media, Facebook COO followed CEO Mark Zuckerberg's example and gave a huge amount of her company stock to charity. Meanwhile, Twitter was under pressure to crack down on hate speech, Snapchat began shopping for ad tech startups, and Foursquare's co-founder and CEO announced he would be stepping down.

It's time for Social Media Sunday!

Facebook

$31 Million from Sheryl Sandberg

This week, Facebook COO Sheryl Sandberg announced she had decided to donate about $31 million worth of her stock in the company to charity, just days after CEO Mark Zuckerberg's similar pledge of over 90 percent of his stock.

The transfer of Sandberg's 290,000 shares in Facebook to the Sheryl Sandberg Philanthropy Fund and other nonprofits were reported to the Securities and Exchange Commission this week.

One group benefiting from Sandberg's giveaway is her women's empowerment group, Lean In, which seeks to support women in the workplace, especially in Silicon Valley.

Messenger Opens to Chatbots

According to a TechCrunch expose, your Messenger inbox may be filled with bots in the near future. That's because, as the anonymously sourced report states, Facebook has a secret chat software development kit (SDK) that allows developers to create artificially intelligent chat bots.

If true, and bots are incorporated in Messenger, those bots could eliminate the need to use other apps for many tasks. For Facebook, keeping users inside their app environment is a major goal.

In this vision of Messenger, users would be able to send questions or requests in plain language, which bots will respond to with the requested information, location services, instant buying opportunities for products, and other digital services. It would change the way we use Messenger, and possibly our mobile devices, since these services have traditionally been sequestered into separate smartphone apps like Uber, Google search, Amazon, and so on.

Twitter

Pressured on ISIS, "Hate Speech"

At the end of last year, Twitter announced an update to its terms of service that the company hoped would tamp down on hate speech.

Clarifying what the company considered "abusive behavior and hateful conduct," Twitter vowed it would not tolerate behavior intended to harass, intimidate, or use fear to silence others. The update also included mandatory actions for users suspected of abusive behavior, such as email and phone verification of accounts and user-prompted deletion of tweets that violate the rules.

But it may not have been enough, because this week, the widow of an American man killed in Jordan from an ISIS attack on police filed a lawsuit against Twitter, blaming the social media company for making it easier for ISIS to spread propaganda.

"Without Twitter, the explosive growth of ISIS over the last few years into the most-feared terrorist group in the world would not have been possible," the complaint reads, according to ABC.

Twitter responded stating, "While we believe the lawsuit is without merit, we are deeply saddened to hear of this family's terrible loss... We have teams around the world actively investigating reports of rule violations, identifying violating conduct, partnering with organizations countering extreme content online, and working with law enforcement entities when appropriate.

Auto-Play Periscope in Your Timeline

Periscope videos will soon play automatically inside of tweets on your feed, if you have an iOS device running the Twitter app, the company announced on Tuesday. According to Mashable, Twitter will roll out the feature on its website and Android devices later.

The feature will bring Twitter's app much closer to Facebook's, in effect, since the company's larger rival has been incorporating auto-play video into users' timelines for a couple of years. It will increase Periscope's reach and engage users with both Twitter and its subsidiary live video-streaming app, Twitter hopes. 

Snapchat

Goes Shopping for Ad Tech 

Snapchat is still serious about advertising, but the company seems to have realized it needs help in that area. According to Re/Code, Snapchat is looking at possible acquisitions of ad tech startups that could help bolster its in-house marketing outreach, and automate its ad sales. The anonymously sourced report hasn't been confirmed by Snapchat.

The move makes sense though. Snapchat is one of the best-funded "unicorn" startups, and despite spending about a year working on its advertising and other revenue streams, those project are still in flux. For example, just months after launching its Lens Store, Snapchat closed it early this year in order to focus more on advertising.

Foursquare

CEO Out, Company at Half Value 

Foursquare just closed a $45 million round of funding, which sounds like great news. But the funding round also put the value of the location-based social media company at half of its previous valuation in 2013, according to the New York Times.

In tandem with that announcement, Foursquare's co-founder and CEO Dennis Crowley announced he would be stepping down from the position.

In a way, he's being kicked up the ladder, as Crowley announced he would become Executive Chairman of the company's board. But he will no longer be making the most important operational decisions, instead promoting former COO Jeff Glueck to the role of CEO.