If you want to download as videos itself, you can use other free tools like Free Youtube Download to download all videos with a single click. Please be careful while installing this tool as it optionally installs a browser toolbar and modifies search preferences. So please make sure you read and uncheck the optional checkboxes while installing to avoid surprises in your browser.
Remember that problem of using Chrome extensions from the Google Web Store? You're going to have an even bigger issue when you want to download from YouTube using an Android app from the Google Play store, where Google has an even tighter grip. (Nor can you actually download anything with your officially sanctioned YouTube apps. Unless you live in India.)
We support videos download from popular video resources. You can download videos from anywhere: Instagram, Vimeo, Youtube, Facebook, VK, DailyMotion, Twitter, Pinterest, Tumblr and many others. Check the images below the text, to find out if the service from where you’d like to download is supported by us. Our database grows every day. We work on adding new sites and improving customer experience. We care about your positive feedback. If you fail to find the website in the list, please contact us immediately and we will be glad to solve the problem and add any of the services needed to download videos.
You just need to copy your preferred playing URL, or right click on the video to select "Copy video URL", then paste the URL into the search box of Distill Video (http://distillvideo.com) and press “Start” button. After waiting 2-3 seconds, the video section showed, choose your preferred format and right click the "Download" button, then click "Save link as..." to download the video or audio into your computer or mobile phone. It supports HD: 1080p, 2k, 4k and 8k. If you are using browsers of the smart phone or tablet, just Touch and hold the "Download" button, then click "Download link" to save the file to your device.