Can I view OS maps for the UK online for free?
I want to see both the Landranger and Explorer maps if possible.
Yes, go to https://www.bing.com/maps/ and select "Ordnance Survey" in the drop-down in the top right corner.
The zoom level you select will show either the 1:50,000 or 1:25,000 map you will see.
Ordnance Survey Maps can be download to a mobile device for free using Avenza PDF Maps. The maps can be viewed without an internet or cellular connection after download. Avenza allows you to store up to 5 maps for free so you can either download them and swap them out or pay for a professional version of the app. https://www.avenzamaps.com/maps/search.html?query=&location_mode=map_input&location=&sort=relevance&price_max=1&page=0&debug=¤t_map_id=&location_box=55.0150538046944%2C-1.5198503796983687%2C54.02605303562811%2C-2.7654253308702437&vendor_ids=&category_ids=&merge_mode=v4&debug_ids=