Chromecast stream iphone airplane

Hi, I bought this app to use with my iPhone 6s and iPad Mini 2.
When I stream a video on my NAS to Chromecast on tv, I can view mkv and mp4 videos…all rigt.
But when I turn off my device (iphone or ipad) or enable airplane mode, video stream on tv is interrupted…it is normal ?
I thought that streaming video to chromecast (infact I bought pro app for 10euro) works with the iPhone off !
Thanks for help.

Totally normal, your iPhone/iPad is connected to your NAS and then stream the movie to your chromecast, if you turn off the wifi from you iPhone/iPad, there is no more connection to your NAS. Your chromecast isn’t able to connect itself to your NAS, it needs your iPhone/iPad.

Thanks for fast reply.
When I use, in Italy, the INFINITY app (service like netflix) I use iphone or ipad only to choose movie and the video streaming is transfered to chromecast (Chromecast – Help Infinity) . In this way I setup the movie on device, on TV video start to play and then I can turn off my device.
if I used the 3rd generation apple tv (this ) I would have the same problem?

No, the Apple TV has a Netflix app, you won’t need any iOS device to stream Netflix