On an Linux based system I created a WLAN Hotspot. I want to provide a single webpage via a webserver on this system. When I connect my Android devices to it they expect to get internet over this connection. But since the Linux host is offline the Android devices are able to see only the webpage and can't reach the internet any longer. I don't want the connected Smartphones to lose their normal connectivity.
Is it technically possible (for example by using any special WLAN settings or Hotspot configuration) to tell Android devices anyhow to use the WLAN connection only for accessing the single hosted webpage and to use their own mobile Internet (cell net) for any other internet access?
This question implies the question if it is possible to use mobile internet via cell network while beeing connected to a WLAN network on Android devices.
The Linux system currently is a Ubuntu Desktop machine and will be a Raspbian (Debian) on a Pi later on.