Microsoft Research's FUSE Labs is making available a new free phone app that makes photo sharing easier.

The new app, Xim (pronounced "Zim"), allows users to share photos across devices without having to pass their phones around.

Users don't need to have the Xim app to see shared photos. But Xim does require (for now) a U.S. phone number, allowing users to use email to "Xim" to anyone with a smartphone. The Xims are viewable in browsers and expire after about an hour.

To create a Xim, a user does need the Xim app. Starting today, October 8, Xim apps are available for Windows Phones and Android phones; an iOS version is coming soon. The Xim creator can choose anywhere from one to up to 50 photos from a camera roll or another third party service like Dropbox, Facebook or Instagram, and then choose whom to invite via a text or emailed invitation.

Those invited into a Xim can swipe, pan and zoom together, according to Microsoft's blog post explaining the new Xim app.

Earlier this summer, there were reports that Microsoft Research was building a Snapchat competitor. It turned out that app, WindUp, was meant to be "for research purposes only," according to Microsoft officials.

Microsoft did make WindUp — which allowed sharing of images, videos, text and audio snippets for "a finite period of time" — available to Windows Phone users. It's not clear from Microsoft's blog post if Xim built on any of WindUp's concepts or technologies.