HELP! with a simple way to rec. wifi in a rv

Hi , i have a small camper and i need some help. I have two small boys that love there ipods and ipads. so what i need is some sort of hardware that will recive a wifi signal from a distance that would be connected to the internet and would let me have a small net work for them to connect too. 

 

Thanks so much for any help..

The only thing that i can think of is getting a mobile hotspot. most mobile carriers have some that you can get, i don't know what the rates are though. there is one that i found very interesting, it's called freedompop and comes with 500MB a month. so that may be an option to look into.

I also searching for a way to set up internet in an RV.  My main access points will be RV resort hot spots which are not really very good.  I have heard that a yagi antenna can do wonders for bringing in poor signals, but I do not know what router to use for PCs, streaming media and wifi on a smart phone.