Today I review the most useable app youtube.this app is very help for me to increase my knowlege in my field this app provide a gud quality concent for their customes.and the best part of this app I seen is their guidelines policy.this policy is very important thing for this app because the age peoples visit youtube every day specially children which watch cartoons.so this policy banned the 18+ videosviolence videosand natural disester videoz.and also youtube provides the high quality videos for their customers + 4k