Not a long period of time when whatsapp start enabling users to share there Microsoft File (txt docs off etc) that ffeature has really help many offices and students users.
Currently not has now updated the feature support all files extension, it may allow you to even share your android Application for only Android and BlackBerry (BB 10) User but not any other platform users like IOS Windows phone, but they can share all other documents.
WhatsApp has also set it so send Any type of files you can think of at all and it currently enables users to share a maximum file size of 100MB (Android), 128MB (iOS) or 64MB (desktop).
It is currently been rolled out to some beta users… with time, it will get to everybody. The roll out of sharing of all file types is for iOS, Android and Windows Phone users!