iPad app timing out and disconnecting

[G man]

I have remote app up and running. It all works fine but when I try to download a reasonable file eg. a movie. I need to sit there and watch it and keep the app active. I need to touch the screen every so often to prevent the iPad timing out as the app disconnects. Also if I try to navigate around whilst downloading the app crashes and disconnects. As soon as it disconnects the download stops. Surely there is something wrong.

Is this normal?