The OS Maps API provides accurate, up-to-date maps that offer the most convenient way to add detailed OS data to your application. This allows you to make location-based decisions with confidence, removing the overhead of managing complex datasets yourself.is a base mapping product provide by Ordnance Survey via the OS DataHub.
There are four styles available: Road, Outdoor, Light and Leisure. Each map style contains OS OpenData and Premium data layers. From iShare v6.0.0 these can be used as a Base Map Maps for iShare Maps or iShare GIS.
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Also under your Geospatial Agreement you will have access to Aerial Photography from Bluesky Mapshop which is free for every local authority.
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Using the OS Maps API in iShare
In order to use the OS Maps API as a Basemap in iShare you need to be on v6.0.0 of iShare which uses MapProxy (instead of Tilecache) as it supports WMTS. Please see Using MapProxy to proxy a WMTS Basemap for details.