I haven't used iNavX so can't comment on that.
We use Navionics on an Android tablet and Garmin Bluecharts on the chartplotters.
As Gaelen said, if you have Navionics and Bluecharts you don't really need anything else (electronically) but as backup we also have
OpenCPN on the tablet and on two Android phones (with old CM93 charts on all three).
We also carry
passage planning paper charts if heading offshore and pilotage guides for areas we'll be heading to but with the
internet the pilotage guides aren't as important as they used to be (assuming you plan ahead and plan for alternative refuges before leaving port/internet access).
Other (Android) apps we use:
NAVTEX
Marine Weather
XCWeather
Windfinder
Ocean Temperature & Tides (NOAA buoy data)
Anchor Watch Pro (Best
anchor alarm app I've tried. It can also send an SMS to a 2nd mobile)
Sky Map (identify stars)
Vessel Lights (Realise how many you've forgot/don't know when you're on watch at night...
)