What alternative do I have without a usable menu button?

[AC Question]

I damaged my Galaxy S4 Active (not as 'waterproof' as advertised) and the menu button no longer works. For the most part, this does not render my phone totally ineffective but unfortunately does limit usability in some apps that still rely on the menu button. So I ask is there an app that can make a "menu" option appear so I can use in context app menus? Or perhaps a softkey that will emulate the button? I've not found one that can actually be a menu button. I'm okay with paid apps and I'm alright with root apps. I can answer other questions if necessary. If this has already been answered, I was unable to find it. Sorry if that's the case. Thanks all!