[Q] WiFi tethering bridge to existing access point
At my girlfriend's house there's an existing WiFi access point for their home network and they also have a bunch of computers wired in with ethernet cable. Mobile reception in the house is terrible but I've found one spot by a window where I can sustain a pretty decent dc-hsdpa link. I'm able to tether my laptop to my phone, the phone creates a new WiFi network ap and my laptop connects to that. That works fine.
The thing is, what I'd really like to do, is to have access to the dc-hsdpa connection from some of the wired computers on her home network. To do that I want to have my phone bridge the house network - via their existing WiFi ap - to the mobile internet connection. I'd like the phone to provide a gateway on the house network that could be manually used from the other computers. (I want to avoid using DHCP or anything as it will disrupt the network for other users.)
I know this is technically possible but I'm struggling to find an application that allows for this functionality. I've spent a good amount of time searching around the internet but to no avail. Does anyone know where I can look or of a suitable application? (My phone is a Samsung Galaxy S4 i9505 flashed to run a rooted variant of the play edition KitKat rom.) I'm happy to pay money.