Visible map & GPS, well for the same reason I use Garmin GPSMAP 78 SC.
Nice little unit, bit thirsty on batteries, from eBay.
Make use the unit comes from local suppliers, otherwise will not have all AUS charts.
Alternatively, go for basic hand held and paper charts.

Cool, cheers guys

I will just get a handheld GPS me thinks.

As far as marine charts go, can anyone recommend a decent one with decent long and lats so i know where i am :P

Are the ones made by the department of transport useful for what i need?

Thanks

iPod or iPad with Bad Elf gps plug in ($100)
Run with navionics or inavx. I prefer inavx
Back up paper chart.
I'd take someone with you whose done the trip b4.

Garmin 76Csx has a bigger screen than the 78 and batteries last longer.

It is very easy to setup waypoints on a PC then upload to the 'device'.

How does Insurance view iPad/iPhone navigation if something goes wrong?

If you want protection for the IPhone I kitesurf with mine in a lifeproof case, not cheap but cheaper than a new phone.
Used on a IPhone 4 & now 5 and never had an issue, waterproof to 2m etc.
www.lifeproof.com/

Bit off topic, but if you have a spare 15mins, check out this TED video.

www.ted.com/talks/todd_humphreys_how_to_fool_a_gps

Fascinating and frightening.

SirJman said..

Anyone try one of the things?
http://www.ozpilot.com.au/GPS/iPad-GPS/GNS-1000-Bluetooth-GPS-Receiver/p-94-314-1154/

Also what are the charts like on the navionics app?

After my iphone 4s told me I was sailing through an island that I was 1km west of (Garden Island, WA) ,
I purchased a very similar gps add on.
The Bad elf gps unit plugs into the charging socket of an ipad or ipad.
The plug in itself has a socket so you can power up the ipad/iphone and the add on gps at the same time.

I believe the ipad has the same gps chip as the iphone 4s - so you have been warned.

Bad elf also makes a wifi version like the one you posted the link to.
I have the small plug in version and one of my mates owns the wifi bad elf version.
Both extremely accurate in the 2 years we've had them.

I prefer inavx to navionics. More functionality - maps basically the same.

bad-elf.com/

I've been using isailer for a year or so now, on the iPad, and seems to copy over to the iPhone via blue tooth or I cloud or something.

Works great, very accurate and was pretty cheap too