I have been using some apps that have this function basically let you have 2 urls one to use locally and one over the internet. First it checks if it is local and if it can't it does it remotely. This could help a lot to the download speed this is usually done before leaving home to save data and so this would be done much faster because locally the speed is usually much higher and also decrease the dependence on the internet if you are at home. I have also seen that to make it faster add a field where you put the SSID of the wifi where you want to use it locally in this way only tries the local connection if you are connected to that SSID if you are not it goes straight to the internet url.
I have been using some apps that have this function basically let you have 2 urls one to use locally and one over the internet. First it checks if it is local and if it can't it does it remotely. This could help a lot to the download speed this is usually done before leaving home to save data and so this would be done much faster because locally the speed is usually much higher and also decrease the dependence on the internet if you are at home. I have also seen that to make it faster add a field where you put the SSID of the wifi where you want to use it locally in this way only tries the local connection if you are connected to that SSID if you are not it goes straight to the internet url.