iMAllFile : let you send any type of file from iMessage with a simple file browser which let you browse the hole filesystem and choose any file to send.
How it works:
● after enabling it from settings, you wil see a new share button on top right of the navigation bar, which will open the filesystem browser.
● and after that you will see an popup menu which have an iMAllFile option click on it and it will let you send the chosen file to your recipient.
The tweak works on both iOS 7 and iOS 8 and can be purchased for $.99 from the Cydia Store.