Tablet for navigation: what works?

[biscuit]

(Amendment: following my post on page 1)
I now find that the VMH android chartset, together with my Antares, have all been effectively wiped after a routine "Upgrade" (an Orwellian piece of doublespeak if ever there was one!) of "Marine Navigator". The VMH instructions to correct this don't seem to work, but when I have a week to spare I will repeat the (to me) very difficult process of reinstalling and merging them.
Antares recommend Memory map, but I find that even more difficult. They should supply a 12 yr old whizz kid to do the installation!

 

[Rivers & creeks]

I have used an iPad as our plotter for the last 4 years. It is a superb piece of kit, does everything I'd want a plotter to do except show class A AIS targets - who wants to see class B - the downside is that bright sunlight on the screen would make it unreadable, it works for us because we have a wheelhouse. Waterproof cases are readily available but can cause overheating on a hot day. The best place on a cockpit yacht would be under a spray hood where it can be shaded and also viewable from the helm. In reality if you want an all weather cockpit plotter it has to be a marine one. but for chart table or wheelhouse the iPad is practically faultless. And when you arrive it works as a TV, radio, ipod, browser etc etc. There are some really good Android powered devices but lets be honest, the iPad is overpriced and has a restrictive OS but Android is not yet a robust and straightforward OS.

 

[gjgm]

The main issue I see is the reflective screens. The Sony Z series are not very intense compared to say Samsung, but then they are waterproof/resistant. I think tablets are reasonably effective as long as you have them shaded, but I would love the know if someone says you really can read them on a bright sunny day.
I have a Nexus and Asus, and most of the time I can't tell if it is actually on or off it is so poor outside.