Snap stock plunged Friday after the social-networking firm posted disappointing revenue growth and guidance that fell shy of estimates on Thursday. The parent of Snapchat said its advertising revenue was hurt more than expected by Apple ‘s change in the rules surrounding advertising on mobile apps. The miss weighed heavy on shares of other major social-media companies. Snap (ticker: SNAP) stock was down 25% in Friday trading. Facebook (FB) was down 6% on the news, while Twitter (TWTR) was off 5%, Pinterest (PINS) had fallen 4.4%, and Alphabet (GOOGL) had slipped 3.4%. Snap is the first of the companies to report September quarter results. For the third quarter, Snap posted revenue of $1.067 billion, up 57% from a year ago, and below the company’s guidance range of $1.07 billion to $1.085 billion. Adjusted Ebitda, or earnings before interest, taxes, depreciation, and amortization, was $174 million, well above its guidance range of $110 million to $120 million. On a non-GAAP basis, the company earned 17 cents a share in the quarter, beating the Street consensus of 8 cents a share. The company said it grew daily average users in the quarter by more than 20% to 306 million.