Snapchat lost around 1.3 billion dollars (£930m) in market value after reality star Kylie Jenner tweeted that she was no longer using the social app.
The half-sister of Kim Kardashian told her more than 24 million Twitter followers: "sooo does anyone else not open Snapchat anyone? Or is it just me... ugh this is so sad."
Shares in Snap - the app's parent company - closed 6% down on the US stock market after Jenner's post, which was in reference to a controversial recent redesign of the photo sharing app.
More that one million people signed a Change.Org petition calling for Snapchat to revert to its previous design, labelling the new version too difficult to use shortly after its launch.
Jenner later tweeted again in defence of the platform.
"still love you tho snap ... my first love," she wrote.
The app's redesign was first announced in November, with founder and chief executive Evan Spiegel calling the change a way of separating the "social" and "media" content areas of the app to allow users to keep friends and family separate from news and public content.
But in response to the online petition, the company said it would make further changes to improve the experience.
"We hear you, and appreciate that you took the time to let us know how you feel. We completely understand the new Snapchat has felt uncomfortable for many," the firm wrote in a post on Change.org.
"Beginning soon on iOS, and with Android in the coming weeks, we are introducing tabs in Friends and Discover, which will make it easier to find the Stories that you want, when you want them.
"This new foundation is just the beginning, and we will always listen closely to find new ways to make the service better for everyone. We are grateful for your enthusiasm and creativity. We are very excited for what's ahead."
Snapchat is facing intense pressure from Facebook and the line of apps in its ownership - including WhatsApp and Instagram - which have adopted Snapchat-like features in recent years to try and entice users to switch services.
At around 180 million people, Snapchat also currently has significantly fewer daily users than Instagram, which currently has more than 500 million.