This is how I setup the backend for the geolocated molecules, using Hoppala to provide hosting and editing for a Layar layer. Layar indexes Points of Interest (POIs) with associated information and URIs. These can then be picked up by the Layar browser on a mobile device, in order to create the 3D overlay on reality. However, Layar doesn't host the files itself; one option is to use Hoppala, which both hosts and allows for easy editing of POIs and metadata. The stages involved are:

• create a Hoppala account, and a layer,
• create a Layar account,
• associate this with the Hoppala layer, and add extra information.

Setup Hoppala[edit]

• Go to the Hoppala site, setup an account and log in.
• Use the dashboard to create a new layer, with a name and title. I think these are internal to Hoppala.

Creating Hoppala layer

• Add some POIs. See this post for one way to do this.

Setup Layar[edit]

• Create an account with Layar, and then visit [1] to register as a layer publisher. Now you should be able to create a layer:

Create a layer

The layer needs a name and title. It also needs to be set to 3D and 2D objects. It also needs to point to the API endpoint of the Hoppala layers we created earlier (you can find this on your Hoppala dashboard).

Create a layar layer

I've then changed or checked the following:

• Listing and Indexing -> allowed Layar to index all POIs. Make sure API version is 3.0 or greater, set a short TTL so they get re-indexed quickly when testing
• Setup the Coverage to surround Cambridge - this can be quite a wide area
• Alter the filter settings so the default range is 5km, and the max is 15km - this should make it easier to see molecules which are distributed around cambridge, and we shouldn't have too many on screen at once.

That should be about it! The layer is now ready for Testing - it will only be available if you explicitly sign in to your Layar account from your phone. Once you've tested it, you can request that it be Approved, at which point I believe it becomes more publicly visible.