If you have an Android phone or tablet (bigger screen) then you could try www.visitmyharbour.com, based in Ryde on the Isle of Wight. They supply digitised charts for UK, France, Western Europe, etc. I joined them a couple of years ago (£25 for life), bought a chartplotter app called Marine Navigator, by Ronald Koenig, from the PlayStore for less than £6 and download all 800+ charts (Admiralty) for the UK for £7.99. These are up-to-date and suitable for navigation. I download a new set every year.You'll find all the info on the website. Apart from the £25 membership (which opens other useful stuff, e.g. blending charts onto Google Earth), my initial bill for setting up the tablet as a plotter was less than £14. It's worth a punt for that price! You don't have to pay the £25 but the charts are a little more expensive (£14.99 from memory). The tablet sits on the binnacle (with a ziploc bag handy for bad weather).
partly a limitation of trying to use an unsecured laptop at sea.