The developers, Pinger, suggest GIF Chat is a good way to communicate something you don't want to post to a social network, in effect promoting it as a private way to swap video messages. It's worth pointing out that the animated GIFs can also be set to loop forever should you wish your message to remain available indefinitely.
Pinger have done a good job implementing GIF Chat, with an emphasis on simplicity and ease of use. The UI is finger friendly, though perhaps a little lacking in options in the recording stage. The first time you use the app you will need to register for the GIF Chat service using your phone number. You will also be prompted to send invitations to friends, encouraging them to join the service, using email and SMS.
GIF Chat has found some success of Android and iOS, but has thus far failed to breakout into the mainstream. That means you are relatively unlikely to find friends already using the service, which severely limits its utility. That's not really likely to change with its arrival on Windows Phone, but it is notable that it arrives on Microsoft's mobile platform just over a month after it was first released on the main competing platforms. And the lift off point for these services can arrive unexpectedly, so it may be worth keeping an eye on the service over the coming months.
Windows Phone Store description:
Send hilarious looping videos like texts. GIF Chat is the first messenger app on Windows Phone that combines animated GIFs with texting. Quickly record videos, add captions and swap them privately with your friends. You determine how many times they can be viewed before they disappear forever. It’s the first app on Windows Phone from Pinger, makers of the #1 free texting and calling app, Textfree.
GIF Chat is a free download from the Windows Phone Store. The app is ad supported.