I mostly use my phone for going on youtube and listening to music but might as well be safe then sorry 
I disabled unknown sources, and as for updating my device for SM-G920W8 (Canadian s6), 5.1.1 is the latest version.You should disable unknown sources and update your device.![]()
adguard helps block ads on the web, and on youtube, and i use the proxy version which requires root. i also use greenify and adaway which require root, also zemana is a good mobile antivirus.If you only use it to listen to music and watch youtube why is it rooted? I would also consider use chrome instead of samsungs browser. And anti-phishing is pointless for users who are tech savvy. I also wouldn't use free vpns because they sell your data, are not secure, and some add you to a botnet. But if you really cant afford one I guess its better to use one then not to use one when on wifi for passing geo restrictions. Just only use it when you must. I would also add a good antivirus such as eset. And on the side I would add kaspersky threat scan and check out some trend micro apps, they protect you from vulnerabilities you can get on a rooted device.