ok, I need a definitive rationale for investing in a dedicated plotter vs. an iPad using Navionics. Recently, my old Raymarine (analogue) plotter packed it in. It was a bit of a tank so I had been using my iPad primarily and have found Navionics to be really very good. I should qualify my question by saying both my fly bridge (most of my piloting) and the lower helm are both fully covered so no weather issues and lighting issues. Pricing new plotters is daunting not only the prices but the wiring and installation. But, I have my iPad with touch screen capability and portable, if needed, and have it powered at either helm. So, why invest in a plotter other than I have two main screens (radar and iPad) instead of one...?