iNavX on iphone and ipad!
Some years back I decided to buy the best handheld I could find so I could easily jump between boats. Just before I pulled the trigger I heard about iNavX from Keith K. At $50 for the app and another $100 for a waterproof iPad case I got off pretty cheap and couldnt be happier. I also have it on my iphone at no extra cost.
When on my boat the Furuno is my primary, the iPad my secondary, and iPhone would be the "Oh S#!+" 3rd nav backup. When out on the skiff I've got iPad as my main and iPhone as backup.
I understand there are subscription capabilities that enable sharing waypoints between devices, weather/conditions overlays etc but I havent looked into the details because the basic app is good enough for me.
Good luck with getting back in good shape. I hope you were able to get you waypoints off the old device before the breakdown.
“There is one thing which gives radiance to everything. It is the idea of something around the corner.” G.K. Chesterton