with a full-sized laptop or even a tablet screen, then you can do that. Vector charts -- not.

The difference is that raster charts are image-based graphic copies of the paper charts. Yes they are the SAME as your paper charts, but they are easy to keep up to date whereas your paper charts aren't. Vector charts are drawn by the device in real-time as you view them, by reconstructing a drawing based on data tables. All C-Ps and the Garmin iPad app use vector charts. (Garmin Blue Charts are vector). Raster charts show all detail (within the limits of the pixel count of the display) when you zoom in and out, and programs that use raster charts seamlessly switch to higher or lower scale NOAA charts as needed. Vector charts contain all the highest detail in the database, but to keep the screen from being too cluttered they don't even try to display smaller items as you zoom out. So they scale differently. Raster charts take a lot more storage space on disk/memory cards than vector charts, but memory is so dense and cheap now it doesn't matter in most applications.

If you have an iPad check out the Skipper app, or try Coastal Explorer on a PC. Both use NOAA raster charts very well, and both can do automatic chart updates when connected to broadband Internet.

http://www.tryskipper.com/

BTW -- Skipper is still a very new app, and I don't recommend it except as a reference and planning tool. It lacks some important features for use underway, but I've exchanged emails with the developer and they're coming. I think it will be a great tool by next sailing season.