iPhone and iPad users will be able to buy items on Pinterest starting later this month.
Actual tweets will appear on mobile devices, depending on the search.
Facebook is reportedly working with game developers to offer their apps in Messenger.
With Stream, users can watch popular videos on Periscope.
The app let users post comments to a feed without their names attached
Tweets might appear in Spotlight searches on Apple devices, Twitter CEO Dick Costolo said.
The feature works over Wi-Fi and LTE, taking aim at other video solutions like Google Hangouts.
Total sales for the first quarter grew by more than 40 percent
Apps like Meerkat and Periscope can lead users astray of privacy and copyright laws
The site also expressly forbids posts with sexual content involving minors.
Marked up Apple Watch models are already available on the e-marketplace, with April and May delivery dates.
But Instagram and Snapchat don't fall too far behind
The price of the service hasn't been revealed, although the plan was disclosed in a YouTube letter to its content partners.
It has many of Messenger's mobile app features, just in a handy Web app format.
Snapchat said it received 375 requests for user data from U.S. authorities between November and February.