What are the best apps to watch full length movies?

iTunes by Apple Inc. is a media player and a library, as well as an internet radio broadcaster, file manager, and a store where users can browse and buy different types of apps and entertainment products like movies and songs.

Vudu is an American company that offers video-on-demand services. It is available to both Android and iOS devices, along with Windows and Mac computers. It has a library that contains both the latest releases and timeless classics. It's only accessible from the US and signing up is free.

YouTube is an online video sharing and streaming website that enables content creators to share their work across the platform's large user base and network. It's also available as an app for Android and iOS mobile devices. 

Tubi TV is an entertainment web application that lets you watch popular movies and TV series. You can stream content in full HD and watch videos on your smart device. The service is free but it is ad-supported.

Hotstar is the premiere video-on-demand streaming service in India that offers Indian TV shows and movies in various language options. It also offers various HBO, Showtime, and Hooq content as part of its streaming catalog.