Adrian, I think Navionics Mobile is a terriffic value and useful for many things, but it's really not meant for primary navigation. If you want to do your main nav on an iPad, take a good look at iNavX. Used with an X-Traverse account, it may give you a choice of Swedish cartography. MemoryMap, and other iPad nav programs, may also offer Swedish charts.
I don't know anything about Stentec, but I do know that there are several PC charting programs that are way more powerful than anything on a mobile device and which support chart for your area. Coastal Explorer 2011, MaxSet TimeZero, Nobeltec VNS 11, and Fugawi ENC are all worth consideration, and there are no doubt others. Sorry for a complicated answer ;-)

Curious, why do you say the Navionics isn't for primary navigation and the iNAVx is?

-p

I do see the Navionics App has a warning "do not use this App you bought for navigation for navigation" on startup and the iNAVX does not.

-p

I suggest you compare the feature lists and screens, Patrick. Navionics displays virtually none of the data fields you might want to have underway, like distance and bearing to waypoint. While iNavX can display most any data including from your vessel's sensors via WiFi, plus AIS targets. Navionics Mobile is great for planning, sharing tracks, etc., but it's not really designed for underway navigation.

AH... I was thinking of using it just for charting and relying on the ships instruments for instrument displays.

-p

iPad is great domestic portable Internet access device and many other exciting android tablets are on the way but none of these were designed for the marine environment and constant exposure to moist salt air. I like the Navionics app, but for fun, I bring it when on cruise liners, but i won't be using it in the cockpit of our boat. Putting iPad in a clunky plastic cover negates half the ergonomics and screen quality that draw folks to it.

In relation to a Laptop or PC, protection from the marine environment is also needed like shock, vibration and salt air. PC plotting software tend offer more physical options for connecting into a vessels instrumentation system, and simply better and more extensive functionality. There are specialist manufacturers that produce marinised and/or ruggedised laptops and PCs, but at a price.

Despite me being an IT gadget fan, personally I still prefer a proper marine chart plotter for primary navigation on board, but use a laptop for passage planning and the other stuff a laptop can do. A secondary or backup could be a smart phone or tablet, or a handheld marine gps plotter. I wouldn't like my families safety to depend on domestic coffee table electronics however 'cool' they are.

Well said, Ocean Froggie. In the forthcoming war of the pads, it may occur to one or another manufacturer to address the needs of the casual sailor, but it is unlikely. A pad that can survive in a soltware environment, be useable in direct sunlight, and have the processing power to provide even the minimal features of a marine chartplotter will sell no better than a minimal marine chartplotter! And in the miniscule numbers that we would buy, it would cost no less.

I recently used my iphone 4 with navionics charts to navigate from the east coast to the caribbean. A power generation problem prompted me to use the minimal power draw iphone over the power hungry chartplotter. I continued to use the iphone once in the caribbean and found the charts to be very accurate and in most cases, more detailed and at least as accurate as the chartplotter charts (which in my case are 2005-6 vintage). I used a waterproof velco arm band type case with soft plastic window when using the phone/charts outside the cabin. The navionics app allows the user to set a route, edit the route by touching/sliding the waypoints, measures distance, and shows heading line and SOG. It also integrates three days of GFS wind model data on the chart if you can download via wifi or cellular signal. Not a lot of bells and whistles compared to fancier navigation packages but very adequate for my needs. I believe the ipad would be even better due to the large screen, if a good waterproof case could be found that would allow touch screen functionality.

Millsource, there is at least one fully waterproof iPad case:

http://www.panbo.com/archives/2011/02/ipad_cases_for_the_boat_some_interesting_apps.html

But that doesn't mean you'll be able to see the screen in sunlight. Can you really see your iPhone4 screen out in the cockpit in the middle of the day?

Also, isn't it true that Navionics Mobile won't give you distance and bearing to next waypoint, which I'm pretty sure was on my first GPS about 20 years ago? I guess I sound like a wet blanket, and I do like iPads and so forth a lot, but I also think that folks are ignoring a lot of shortcomings in their enthusiasm about them.

I use a Garmin 400c mounted on the binnacle for course, distance, bearing to waypoint, etc. while underway. For everything else, I use an ipad or a paper chart. If I was going to use an iDevice underway, it'd probably be an iphone with a waterproof cover (there are several). Though I've just ordered a scanstrut waterproof ipad case. iDevices can be hard to read in bright daylight, but I haven't found that to be a major issue in practice, probably because I mostly do my planning down below. Navionics is great for planning, but I'd probably use iNavX while underway. Garmin also has an ios app in the works which they say will be out this summer.

A lot depends on your expectations and how you navigate or intend to use the device and/or app. iDevices are way better than a chart plotters in some cases, not so good in others. Can they be a replacement for a "standard" chart plotter, absolutely.

I read more and more often about sailors using idevices effectively during extended journeys. Standard plotters are not about to go extinct, but I know already that I'll never buy one.

I used my iPad with iSailor quite a bit last year and found it to be excellent. Nevertheless, I did feel a bit uncomfortable using it as my primary navigation device. I will continue to keep the iPad fully charged and ready as an emergency backup since I like the redundancy of a totally separate system that does not rely at all on the boat's electrical system or any other electronics (same reason I keep a fully charged handheld VHF).

-Dan

I used my iPad with iSailor quite a bit last year and found it to be excellent. Nevertheless, I did feel a bit uncomfortable using it as my primary navigation device. I will continue to keep the iPad fully charged and ready as an emergency backup since I like the redundancy of a totally separate system that does not rely at all on the boat's electrical system or any other electronics (same reason I keep a fully charged handheld VHF).

-Dan