Is it normal that my bf downloads a lot of porno everyday?

Hi guys, I'm new here and forgive me if I don't spell something right (Spanish is my first language). SORRY IF IT IS LONG ;/ PLIS HELP!!
So here is my problem. I've been with my bf for 1yr9mo but recently I've found out that he had about 20 pages on twitter of naked girls and well porn, and I know he watches porn & don't have a problem with it because I do 2 sometimes. But for me 20 pages is too much, also he downloads about 15 new porn videos everyday mostly at work(security guard). So when I found out about this I confronted him because that's something I don't like. He deleted it all even the twitter(even tho I didn't ask him to) and told me he was going to stop downloading, I told him that I don't have a problem with him watching porn occasionally, and we were ok with that. Last week downloading a song in his phone I saw about 30 porn videos downloaded in 3 days (all while he was at work, and then deleted them, or at least I thought) so again I confronted him, I know porn has nothing to do with me, he is very good with me and we have no problem in the sex department, but again is something I don't like. He told me that he doesn't watch them all and that he erased them, but today I have his phone and was about to download an app(game) when I open the app store there's a gallery vault installed and is hidden (so if I don't open the app store I would have never found out), I know how to open this and the password he usually uses so I tried one and it work. Turns out that 22 porn videos are saved there (the ones he promise (again) he deleted and wouldn't do again) so I don't know what to think or what to do? Sometimes I think is normal, but should I be worried in the fact that he is lying to me about it and making promises over and over again about the same thing and never coming through?