How could one serve maps (tiles in wherever format possible) within a Android device to be consumed by an offline webmapping app also accessed within the device's browser?
Your webmapping offline code (HTML5 + JS) will be located in the
You can put your tiles (XYZ or TMS) in a folder hierarchy inside
Assets, too, and access your tiles via relative paths.
You really don't need a web server, the same way you don't need it to import a JS file into your HTML5 page.