How to download 360 video to Android device's Streaming assets folder, before playback using Easy Movie Texture.

I'm having difficulty finding the information i need to make this work. I hope someone can point me in the right direction.

I'm integrating 360 video in Unity 3d to create a vr-application where the main content consists of four 360 videos which tell a story. The player needs to navigate through the video's by pressing UI buttons.

Since i've successfully built the application by storing the video's natively in Streaming Assets folder, my app exceeds the 100Mb playstore limit because the video's are stored in Streaming Assets.

I'm looking for a way to embed some sort of link to an online source, so the user can download all video content when the app is launched for the 1st time.

So the video will be hosted online. The app will need a link to download the video's and store them on the device. Then the app needs to play the video's from local folders location.

I hope i've made what i'm trying to do here a bit clear. Any help would be much appreciated.