Sweetgreen's website and app crashed during the lunch rush, and customers are freaking out

• Sweetgreen's website and app crashed during lunchtime hours on the East Coast, and angry customers have taken to social media to complain. 
• Sweetgreen is known for drawing long lines at lunchtime. In 2016, it launched its app to enable customers to pre-order and collect salads to take the pressure off in-store ordering. 
• The salad chain recently raised $200 million in a new round of funding led by Fidelity Investments. It is now reportedly valued at over $1 billion.

Sweetgreen's mobile ordering system is temporarily down, and customers aren't too happy about it. 

Dozens of hungry customers tweeted during East Coast lunchtime hours on Monday that they were having problems placing orders via its website and app. 

A spokesperson for Sweetgreen did not immediately respond to Business Insider's request for comment. 

Sweetgreen, which is known for drawing long lines at lunchtime, launched its app in 2016 to enable customers to pre-order salads and collect them in-store. The idea was to take the pressure of in-store ordering and reduce wait times.

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In November, the chain announced it had raised $200 million in a round of funding led by Fidelity Investments, bringing its total funding to $365 million. It is now reportedly valued at over $1 billion.

Jonathan Neman, co-founder and CEO of Sweetgreen, said in a statement to the press at the time: "Our vision is to evolve from a restaurant company to a food platform that builds healthier communities around the world."

The company plans to use the funding to invest in its app, open new locations, and expand its new Outpost service, a new no-fee delivery system in corporate offices. 15 locations are currently operating this new service. Neman told Forbes that the company could have more than 2,000 in place by the end of next year.