read the description and dont expect anything more
the app does only what is described in the description, it doenst provide any added security feature.
There are about 50 backgrounds you can use as a lockscreen, but lets be honest, pretty much everyone knows how iphones work and they orobably wont be fooled. Half the pictures arent even lock related, more like just fluff to bloat the number. So if you want to buy the app for the wallpapers be my guest, but keep in mind you can definitely find better ones simply by searching them on the web.
Prystnk about
Best Lock Security: Phone Passcode