Send GIF in Text Message

I am trying to find a way to send an animated gif in a text message form Unity. I cannot find anything in the asset store or online that provides this functionality. I know it is possible as I have several apps that let me send an animated gif as a text message (or MMS) from directly within the app. Can anyone point me in the direction of where I can get more information/code/plugin to do this? I am interested in support for both iOS and Android.

Thank You!