Stripe, a startup already valued at $5 billion, just introduced easy-to-use tools that enable retailers to sell goods on Twitter and e-commerce apps including ShopStyle and Spring. Dubbed Relay, the new tools strip away the complications and expense of adding a “buy button” on Twitter and other apps. Stripe says a retailer can add that button with Relay in as little as 30 seconds. In addition to Twitter, Stripe has also partnered with Facebook and Pinterest, although neither company has yet to launch Relay.

According to The Wall Street Journal, investors, led by Visa and venture capital firm Kleiner Perkins Caulfield & Byers, injected more cash into the company in July, in anticipation that Stripe would “expand into more areas of commerce and expand into new international markets.” Existing investors include Sequoia Capital and American Express.

In addition to Twitter, eyeglass vendor Warby Parker and Saks Fifth Avenue have also added Relay as another way of moving product. Stripe is already powering payments on 20,000 retailers’ online stores, making them likely adopters of Relay for purchases on social sites and apps.

The cost of using Stripe on new platforms is identical to its current service: Stripe takes 30 cents in addition to 2.9 percent of each transaction.

As it stands now, Stripe only supports transactions in U.S. dollars and all purchases must be shipped to a U.S. address. WSJ notes that, “Twitter won’t receive a cut of the transactions, but will seek to do so at some point as the tool becomes more widely adopted by merchants.”

Twitter executive Nathan Hubbard reports that “50 million tweets each month in which users say they want or need something.”