Norgeskart has recently published a variety of on-line great mapping services for PC as well as for Android and Iphone
based units. See screenshot from my Galaxy 10.1 Tab below.
In addittion to nautical charts
,you can have a combination of detailed topo charts
in colour or b&w,even with optional sea depth
You can select the charts in full screen
mode with no disturbing ads or other unwanted objects. The cross-icon in the centre of the screen
displays the geographical position in decimal degrees down in the bottom left corner.
Although you are not meant to,it is easy to copy and convert to a living .kap format sea chart using MapCal II and GE2KAP.
Again,another POI link I certainly will include in my Norway
POI group in OpenCPN
for quick access to detailed info.Something I have already done with GeoGarage as you can read about in the OCPN section GeoGarage access from Opencpn