Possibly something dodgy...
My recommendation to most people is just get a freesat box (loads of FREE satellite channels, totally legit).. The latest Freesat boxes support netflix (not expensive, month by month subscription so you can turn on/off as needed (eg summer off winter on) and provides tons of content!
Currently we are on an Amazon fire tv box, pay for prime (£70 the year) plus netflix (£8 a month) and it aggregates it all into one easily searched service... No more adverts, no waiting around for your program to be on (its all available now and streamable)
Never heard of Frog Box and a quick search it looks like another one of the snide boxes that pirates content (so could be switched off the day after purchase and you would have no recourse).