I love this app! Its extremely easy to use (my 21 month old can use it by herself). There is a great variety of shows on the app, and its constantly updating so theres new content rotating in. And its completely free.
Just be careful - this app will go through data like Cookie Monster goes through cookies. I use it when we are out at my oldests soccer practice and this season has killed my data plan. It can easily burn through a gig in a couple hours.
Amanda1226 about PBS KIDS Video