Facebook-owned Instagram ramped up the pressure on Snapchat on Monday, adding ephemeral live video broadcasts and vanishing direct messages.
"Send anything you want, from inside jokes to your worst selfies," Instagram said in a blog post.
"Unlike other messages in Direct, these photos and videos disappear from your friends' inboxes after they have seen them."
The updates appeared aimed at getting people to use Instagram more for casual, quirky moments instead of seeing it as a platform for sharing life highlights or polished posts meant to linger.
"Now, you can send disappearing photos and videos directly to groups and individual friends in a spontaneous, pressure-free way," Instagram said.
The option to broadcast live on Instagram follows in the footsteps of a Facebook Live feature, and is a challenge to Twitter real-time video streaming service Periscope.
Instagram live video broadcasts are not saved, so can only be viewed while they are taking place "so you can feel more comfortable sharing anything, anytime," according to the photo and video sharing service.
Instagram said that more than 300 million of its approximately half-a-billion users around the world use its Direct messaging monthly.
Facebook last week said that it has bought facial recognition startup FacioMetrics, potentially using the technology for photo or video effects to better challenge rival Snapchat.
Silicon Valley-based Facebook did not disclose financial terms of the deal to buy FacioMetrics, which was founded in 2015 and specializes in using artificial intelligence to give facial image analysis capabilities to applications that run on smartphones.
Using FacioMetrics to let users of Facebook, or subsidiaries such as Instagram, have fun with photos or video could be a counter-move to those kinds of features offered in "filters" at vanishing message service Snapchat.
Parent company Snap estimates it has more than 100 million users globally of the service for sending videos, images and text messages which vanish after being viewed. Some reports say it generates 10 billion video views per day.
Since trying unsuccessfully to buy Southern California-based Snapchat several years ago, Facebook has turned to cloning popular features.