A caveat for using iPad for navigation apps— the iPad Pro 12.9” cell enabled models have a flaw such that the native GPS is not reliable. I use an iPad Pro 12.9” because I like the large display. In fact, I carry two, one primary, one backup, one cell enabled, one not. The GPS flaw hasn’t really affected me because I use a Dual 160 Bluetooth GPS for position. It can supply position information for up to five devices simultaneously.
The apps I use are Aqua Maps, Navionics, and SEAiq USA. SEAiq USA gives me paper charts on a screen that change scale as they are zoomed in or out. They are updated weekly. Aqua Maps and Navionics both have proprietary cartography and highly accurate depth information, tide and current information. Aqua Maps displays both Active Captain and Waterway Guides information. Navionics displays Active Captain only, but has an auto routing feature that I have found useful. Aqua Maps and Navionics charts are updated constantly.
I do not carry paper charts. Before jumping on me, SEAiq USA cartography IS the paper charts, just presented on a screen. The biggest difference is that paper charts are out of date before they hit the store shelves. SEAiq USA charts receive weekly updates as they become available. They are ALWAYS up to date.
What really convinced me that I could do fine without paper charts is this: Last summer, I concluded a flying career. The last several years of that career, there were no paper charts in the cockpit, just two commercial, off-the-shelf iPads that contained all en route and approach charts plus all company manuals. My iPad took the place of 20 pounds of paper that had to be updated page-by-page weekly. With the iPad, it was a touch of a button. I flew worldwide with the iPad with nary a problem.
So if you are hard-over on “must have paper charts to be safe”, don’t get on an airplane.