you must have localcast on your android phone or tablet ....

this is how you set up localcast to stream to Roku
download localcast from google play store

click on local cast
click on gold button
click on change
discovery options
search for
dlna (smart tv,xbox,and much more )

Roku (check box)

apple tv

click on ok

now open up cartoon hd app
click on movie you want to watch
click on video ..
then click on custom
click on local cast
this might take a few seconds
click on play
you will see it on the Roku ...then the movie will play

this will also set up on showbox ..and you can use allcast instead of using localcast