I personally have used Movieberry.com to download movies and Tv series episodes for many years. You set up an account, load funds on to it, and start buying/downloading. Movies can be purchased in HD resolution or small file sizes that are sized for phones/iPads.

I download them to my computer or android phone and then transfer them to a SanDisk WiFi USB device. (See partisl link below. Just add www.)

It recharges via any USB charging block or computer port and creates it's own wifi network upon turning it on up to 5 devices can connect at one time. You can set up a password.

Mine is a 32GB drive. I currently have about 40 movies, plus with files and images upon it.

My husband, son and neighbor liked it so much, that they all bought one for their own use (school files, work files, movies, go pro video transfers, hunting trips/game camera video and photos, gaming files.)
Amazon has16GB-256GB size drives. I can't post the full link. Add the www. To the front of the link)
​amazon.com/dp/B00ZCFYF2W/ref=cm_sw_r_other_apa_.kUKAbGJQFQ20

Happy traveling and watching!!