Have you tried searching in the tutorials?
https://www.scirra.com/tutorials/search?q=swipe
Generally speaking you'll have a friction type value that would always be reducing the object's velocity towards 0 at a constant amount, and then its just a matter of setting the initial speed based on your swipe.
The basic logic for that is that every tick you will record the position of the object in variables, and you can compare the objects position at the current tick with the last tick when you release the object. The distance between these two points can be used to set your starting velocity.