Openstreetmap Data with OpenLayers vs google maps?

Question

I am trying to use a map provider. I wanted to know which of these is better. Until now, all the reading I have done indicates OSM data is better. Mainly for, It's OPEN & off-line usability. But couldn't get a proper take on which Layer to use.

How are the API supports? Which tiles to use? (mapnik used by openstreetmaps seems to be nice & free)

OpenStreetMaps Tile usage policy(http://wiki.openstreetmap.org/wiki/Tile_usage_policy) does say limited usage.

Which other slippy map layers are good/better with openstreetmaps (free/paid).

My requirements are:

• To allow users to query for routes.
• To allow users to look for a location based on GPS co-ordinates.
• Add a layer to display a set of some of my data based on location.

Answer 1

OpenSteetMap data is better in the sense that:

1. It's free and open.
2. the data is being provided by thousands of users and it's more precise and covers much more information than Google maps data. (except for the satellite view which doesn't exist in OSM).

Tiles - depends on the application you would like to build. For a small (not a high number of http requests) web application you can use the web API which is highly documented and reliable.

The real advantage of OpeenStreetMap, is using OSM data and a number of tools to built you're own OSM server (a good article here), and to use Mapnik or Osmarender tiles render engines for generating you're own tiles that can be used on web applications. This is why the Tile limitation usage exists, because they recommend hosting and using your own server tiles.

The main difference between Mapnik and Osmrender is that the second exports SVG tiles format.

Information regarding your requirements:

A. routing

It's possible to use OSM data to build a routing web application. Here is a list of routing programs and web services on OpenStreetMap wiki

Here are two websites using routing with OpenStreetMap which can give you an idea of how it's used on web applications:

• yournavigation.org

• openrouteservice.org

B. search by gps coordinates

You can use reverse-geocoding and query the OSM database for GPS coordinates the Nominatim tool.

Here is a web application using this tool.

C. layers

Here is the list of webmaps libraries that you can use.

OpenLayers can work with Mapnik generated tiles and it's a commonly used library (with no server-side dependencies) with plenty of docs. It's a framework that can be used as well with Google maps, so it's worth giving it a try.

Polymaps integrates well with SVG tiles generated be Osmarender. It can generate display / diagrams / of specific areas based on marker - user location.