Youtube Video Downloader - TubeSaver lets you download videos from YouTube, Instagram, Facebook, Viewster, LiveLeak, 9GAG, and Tumblr. All you have to do is tap on the option you want, connect your profile, and browse in the same way you would on the official app. When you find the video you want to download, all you have to do is tap the arrow you see on the bottom right and select the format you want to save it in. In just a few seconds, the video will be saved to your smartphone so you can watch it even when you're offline.
This tool is specially designed to make it easy to use, so you can browse your favorite sites without having to open all the official apps. Then, when you find a video you like, you can download it without using a third-party tool.