This is a FREE app with European coverage that includes the UK/Ireland, Germany and the Netherlands, with charts that are easy to read.

The nautical charts app is derived from RNCs published by UKHO,

There’s a satellite overlay, road atlas and custom depth shading. Waypoints and routes can be imported, exported and easily set up, it records your track and allows you to query details about charted objects and it also features autoguidance with voice prompts.

Premium features are available for a charge.