Soon I will be on a long road trip with no wifi. I'm hoping to load up an iPad with a bunch of Amazon prime videos (Netflix and Hulu don't allow this). Unfortunately, I'm stuck with a 32GB iPad (2015). I'm looking at getting some external storage - like the Leaf iBridge or the Sandisk ixpand. Everything I read, though, says to use the storage, you need to use their app on the iPad. Is there a way to use the external storage to save the amazon prime videos? Thank you!