How to get an Internet volunteer project (like Wikipedia) - i.e.local guided tours via cellphones kick started?

The first step is to show your commitment to the project by putting in some work yourself, then ask for help from users and the community as a whole. I haven't really messed with this much, but I know Google Maps has an ability to create custom maps. Since standard Google Maps materials are commonly incorporated into Android apps, I'd bet you could put together an app that allowed custom maps to be imported. That would be a good first step. There's no reason you'd need specialized hardware for anything. I'm not much of a guided tour type on the whole, but I might use a specialty type product (historical, ghost sightings), and I'd certainly use a community generated guide program that was able to distinguish by contributor. There are a lot of tools out there that list bars and restaurants, but not so many that will let you sort them by the crowd they attract. Knowing the type of place a specific contributor likes to hang out would let you pick the vibe a little better.