Hi sir..with samsung smart tv you rely solely on App... Right now u can only cast youtube from you mobile correct... With chromecast you can cast all of app that support google cast...such spotify,  iflix, netflix, facebook and many more.... If your only care for youtube, dont buy the chromecast...but if you want to cast your nephew singing let it go on your facebook post....chromecast js the way to go.... On the other hand topup abit and get the androive tv mi box from xiaomi... Got built in chromecast inside..