WhatsApp is launching a new service for businesses to communicate directly with their customers.
The messaging system is one of several platforms where Meta has launched more shopping-focused features.
Cloud-based software that enables apps to communicate with each other, will open up WhatsApp to more businesses and will be free for smaller firms.
Meta chief executive Mark Zuckerberg said the development would help companies customise their experience.
"The best business experiences meet people where they are," he said at the announcement of the new service.
"Already more than one billion users connect with a business account across our messaging services every week.
"They're reaching out for help to find products and services and to buy anything from big-ticket items to everyday goods."
The service uses an API (application programming interface) - software that allows two apps to talk to each other.
In this case, it would enable customers to click on, for example, "customer service" on a company website to launch a WhatsApp conversation.
Businesses will be able to build a customised dashboard to chat with shoppers and offer customer services more easily.
The API will allow businesses to engage in customer-service chats on the service, which generates revenue for Meta.
By charging on a per-message basis, it is one of the key ways the usually free WhatsApp can make money.
Tens of thousands of businesses have previously been set up on the non-cloud version, including Vodafone, BMW and KLM.
Meta, which bought WhatsApp for $19bn in 2014, said businesses would not be able to message people on WhatsApp unless they had requested contact.
WhatsApp also said it was planning to provide optional paid features as part of a new premium service.
Those features, which are currently being developed, will include managing chats across up to 10 devices and click-to-chat links that businesses can share with customers.