How To Download YouTube Videos on Android

Have you ever wanted to download YouTube videos to your Gallery? I'll teach you how!
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First, open your Android and open the Internet.
Search 'SlideMe .apk download' on Google.
Find a website that you trust and Download.
Now open your Settings app. Find the Security tab, and open it.
The option 'Unknown Sources' should be checked off. Un-check it. Now, open a File Manager, and open a folder called 'Download'. There should be a file called 'SlideMe.apk', and tap Open and Install.
Open SlideMe and search TubeMate, and install. Do the same thing as you did to install SlideMe.
Now, when you open TubeMate, search a video on YouTube, tap on it, press the green arrow, and select the 640x360 (MP4) option, and press Download.
Now after it installs, it should be in your gallery.
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[NOTES]
If you have T-Mobile, then Lookout should be pre-installed, and it will say SlideMe, and TubeMate are Riskware. Ignore that, it says all files downloaded from the Internet are Riskware.
This won't work on iOS.
If the 640x360 (MP4) option is unsupported by your phone, use any option lower then that.