I have read your question several times and I am a little confused. But, I will do my best to give an answer that I hope will help. You want to manage video recordings from several cameras and the only place you can do that is using the mobile app which you do not want to use.
I will use NCS X to show how to manage recordings. You can also run NCS as a service and then use NCS Client. It will be the same. I will also show how you can use the Web client to view and download recordings to a desktop computer or in the browser of your cell phone. So here it goes.
Here is NCS X running with several cameras and I will show 2 of them here.
To manage the recordings from these cameras you go to the Library, red arrow pointing on the Library icon in the top menu
There you have recorded videos from motion detection from all cameras.. Double click on a recording and it will open in VLC.
You can download the video to your computer by selecting the video and click on the download icon in the menu
When you go to the Library by default all cameras will show up, but you can select which camera and also date
The Settings of the Library is show here
In my case I have my Library on the Desktop in a folder called NCS. On the left hand side you see WIndows Explorer. In the folder NCS the files are structured in Recordings and then by date. The recording are named as from which camera, date, time and then an internal number that is used for organisation and in the database.
If you click on a recording here it will show in the default video player for your system. The files are stored in mp4.
This is the organisation of the recordings using NCS.
If you login to NCS using the web client it looks like this with the IP number to the computer running NCS and port 8100. A dialog box will appear where you enter logins. In the menu on the left hand side click on Library and the Gallery and will have all the recorded files again.
By default recordings from all the cameras are show, but you can select which camera, date and for how many days it will show.
When you click on a file it will show and start playing. You can download that file by clinking on the down load arrow in the bottom right corner.
These are the basics how you manage recordings from many cameras. How it works with the Mobile App are you already familiar with so I will not show that here.
I hope this helps. More questions you know where to find me,