SAN FRANCISCO (AP) — Facebook is trying to mold its Messenger app into a more versatile communications channel as smartphones create new ways for people to connect with friends and businesses beyond the walls of the company's ubiquitous social network.

To pull it off, Facebook Inc. is opening Messenger so outside programmers can build features tailored for the service. Messenger will also be adding the ability to display store receipts and shipping information to help consumers keep track of their interactions with merchants and other businesses.

Facebook CEO Mark Zuckerberg touted the Messenger expansion Wednesday during his opening speech at a two-day conference for developers in San Francisco.

The push to plant more features in Messenger underscores the growing importance of apps that enable more intimate and direct conversations than social networks.