Twitter and Foursquare both said Thursday that some high-ranking executives would be stepping down, with the changes coming as both companies look to expand and try out new products.

Twitter said in a regulatory filing that Senior Vice President of Engineering Christopher Fry would be leaving, effective immediately, and shifting to an advisory role at the company, after just over a year on the job. Twitter did not say why he was leaving. The company said Alexander Roetter, currently vice president of engineering, would replace him.

Fry confirmed the news in a tweet of his own. Twitter declined to comment further.

Roetter has been with Twitter since 2010 and currently runs the company's advertiser, publisher and exchange engineering team.

Foursquare, meanwhile, said that Evan Cohen, its chief operating officer and the company's sixth employee, would be leaving at the end of June. Jeff Glueck, formerly CEO at mobile cloud computing company Skyfire and chief marketing officer at Travelocity, will take his place.

In addition, Holger Luedorf, who has led business development efforts at Foursquare for the past four years, is leaving Friday for the on-demand delivery company Postmates. He will be replaced by Mike Harkey, who has served in a business development role at Foursquare since 2012.

"Evan and Holger have been instrumental in growing Foursquare from a small shop to a company employing more than 170 people worldwide -- without them we wouldn't be where we are today," a company spokesman said.

For Foursquare today, that place is a crossroads. The company was one of the most closely watched social media startups a few years ago but now is struggling to find its niche. Foursquare's location check-in service was big when it launched, but as mobile has grown over the years, other social networking, messaging and discovery apps have flooded the landscape.

In an attempt to reinvigorate its service and gain new users, Foursquare recently split its app in two. A new app, Swarm, provides a messaging service and a way to see nearby friends. The main Foursquare app will pivot to focus more on location discovery, potentially presenting a new rival to Yelp.

Foursquare's executive departures come at a precarious time for the company, but new blood might be just what the company needs.

Twitter, for its part, is trying to appeal to a more mainstream audience since becoming a public company last year. The company's chief executive, Dick Costolo, says he wants to speed up product development. Engineering plays a big part in that, so Fry's departure could signal a stronger effort to move fast.

Costolo said this week at the Code Conference in Los Angeles that the company was experimenting with new ways to surface more relevant tweets for users.

.WANG DOMAIN HOT SALE

- See more at: http://www.eranet.com