AP-Hotspot
While it may still work, AP-Hotspot is abandoned. That's because there are too many things that depend on the hardware and since I can only test it on one device, that makes the script unreliable for others and for me, pretty much impossible to fix some issues.
For a more currently maintained project, take a look at create_ap. https://github.com/oblique/create_ap
Automatically creates an infrastructure (Access Point mode) wireless hotspot in Ubuntu that should work with Android and Windows Phone devices