Facebook is launching a pay system across Facebook, Messenger, Instagram, WhatsApp

Facebook Inc. just dove into payment systems with a service across Facebook, Messenger, Instagram, and WhatsApp. Facebook Pay, announced in a blog post Tuesday, consolidates its massive social media applications more tightly at a time when politicians and some lawmakers are calling for the company to be broken up. "Facebook Pay is part of our ongoing work to make commerce more convenient, accessible and secure for people on our apps," Deborah Liu, vice president of marketplace and commerce, said in the post. The payment-processing service, considered a competitor to Apple Inc.'s Apple Pay and Square Inc. , begins rolling out this week on Facebook and Messenger. Facebook shares are up 48% this year. The S&P 500 index is up 23% this year.

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