When you when you download a texture pack it should remain in a folder that is meant for those packs and not have to RE download them.

I am playing MCPE on my HTC Adreno ( HTCD660LVWPP, Adreno (TM) 304) Android 6.0.1 and am seeing that the Fantasy texture pack does not remain downloaded or is not recognized by the game as being downloaded after I have played with the texture pack more than once. See screenshot. I do not know where to find the folder for the texture pack or I would see if it was there and downloaded as it should be or I would and screenshot that as well. I have noticed this on both versions recently. 1.0.6.0 and the current version. I don't own any other texture packs at this point to test this out to be true but this does relate to another Issue that I have seen .