Just out of curiosity: Whats the use case to download videos from surveillance to your phone?

You could try Frigate NVR in a docker container and see how it works for you. Easy to spin up. I'm running it in container, passing through my intel GPU for detection, and using hardware acceleration and it works pretty good. Good documentation for Reolink, too.

And since it's ffmpeg under the hood, you could theoretically output to an IOS friendly format:

https://docs.frigate.video/configuration/camera_specific/#reolink-cameras

TBH it was a little bit of a learning curve for me to get the right config only after plenty of trial and error but I'm pretty happy with how it's working.

I have Frigate-Proxy set up on HA which notifies on motion. Pretty slick.

I use xeoma. Its very lightweight