The only place I could find delta browser is in the play store. Open the Google play store and select the 3 horizontal bars at the top left side. On the menu that opens select my Apps and games. Once that is open select the tab titled installed. Scroll down the list, find the app delta browser, tap it and select uninstall.
It really should be listed in system settings apps. It's suspicious if it's not there.
I searched the Samsung galaxy store and it's never heard of it. The search option doesn't get past delta and then goes blank. The only thing it shows for delta are a few games.