I know, I know. I can already hear the thunder upon my
head. It's not safe, it's only a backup, it will break, get wet, etc.
Well, with all due respect, if this reflects somehow what you think, if you belong to the category that has a backup of the backup of the backup of the
GPS just in case, please do not bother reading this thread. Cause whether you think it's a good idea or not, that's my plan. A tablet to replace it ALL:
GPS,
knotmeter,
windvane indicator, you name it.
This said, despite being completely irresponsible, I still could take some
advice. But only on the choice of the tablet and the apps.
So here is my situation, and my expectations, and also some information collected through hours of
research that maybe others will be interested in getting. I don't believe in all the "fancy"
marine electronics. I tried it and I'm not impressed. Much more impressed by an
iPad. So, as time has come to replace most of mine, I decided that 2013 would be the year of a total revolution for my
boat, with 3 goals.
1- no more thru-hulls
2- simple, simplistic, minimum setup. This is worth GOLD to me. Being able to regroup 3 to 5
instruments in one
cheap device easily replaceable, anywhere, is invaluable. Not having
cables everywhere is invaluable. Not having always something to
repair is invaluable. Plus, it looks sleek and neat. And it evolves lightning-fast. New apps, improved performance, lower prices. So it not lasting 10 years is almost better.
3- I'm done paying more because it's written "marine" on it.
In order to achieve these goals, I'll try to have everything except for the
autopilot and the
depth measurements handled by a tablet(s).
actually, the
autopilot could technically be handled by a tablet for everything but the drive unit and they are ripping us off with the prices of
marine autopilots but let's not go there)
- For the
depth, an in-hull
transducer and a
cheap display seems to be still the most simple and reversible setup (all in all, achievable for under $200, with NASA clipper,
shopping directly in UK, if you are interested in avoiding thru-hulls and ridiculously expensive transducers and displays. When you think about it, the
raymarine display at $400 works as a big analog watch, $10 at walmart, so they are really pushing it)
- For the autopilot, there is no cheap alternative here unless you are an extremely skilled and smart and well equipped
DIY. I wish I could have gone for a
windvane, but 7 grand to feel one with the
wind feels like too much to me. therefore, SPX-5 by
raymarine, ($1,200).
- A tablet for everything else. It's actually packed with more features than most marine
electronics. Almost all tablet (except the
iPad in versions other than a 3G) have a GPS, that works without coverage, without
contract, anywhere. On top of that, many tablets have a gyro, an accelerometer, a
compass, and tons of fancy sensors that can provide useful information on a
boat, like the speed, the heading, the heeling angle, even the
wind direction and speed. Of course, not precise enough to participate to the America's cup, but for the others, it will do.
However, 3 questions are essentials to make the use of a tablet worth.
1/ will it withstand the harsh marine
environment?
2/ will it be accurate enough to provide useful data?
3/ display> what apps?
1/ I'm confident that it is. Making a waterproof, shockproof, sunproof and allowing permanent charge (essential!) housing for the tablet is doable for less than $200 (or can be purchased for between $150 for a simple waterproof hardcase and $420 for the fully ready Andres case by DND allowing charge and mounting) . waterproof cases in treated polycarbonate meant to be in a marine
environment are available for under $50 (why are the navpods $400 remains a metaphysical question to me) and adapting them to the ipad cant be that hard.The tablet would still be removable, and if I do it well, will turn upside down and 360. Then, I have a
screen that is bigger than most GPS/ chartplotters, with a lot more capabilities. The quality of the
screen for outdoor viewing is questionable with some tablets, but so it is with some marine GPS. Any experience with tablets screens? any better than others, any to avoid?
2/ accuracy. Here it gets more complicated. it seems that all sensors are pretty accurate in iPads for example, and are used extensively by pilots in small planes. However, GPS chips in tablets have an unknown update rate. It *seems* that most have an 1hz, which means if I get it right that they update the information every second. This is ok for holding a course, but not very good for speed indication, and especially for recording changes in speed as a
transducer would. There are some external devices that allow to enhance the GPS refresh rate up to 10hz, which becomes serious stuff (bad elf pro, emprum GPS, about $150). The best I found were aimed at the apple market exclusively, unfortunately for androids (but maybe they don't need it?). This makes it fast enough to
record the effect of a change in trim
sails. However, it adds a layer of complexity, and most of these device
work on rechargeable
battery, which I don't personally like. I was hoping for a tablet with a better GPS than 1hz. Anyone?
However and FYI, it seems that marine GPS are not any better at refreshing data. Very few GPS are above 1hz. There are examples of GPS used for recording speed and changes in speed aimed at boaters, the best being the speedpuck by Velocitek, that does it perfectly well (but is handheld, and
battery powered, and ridiculously expensive). Therefore, there is absolutely no point in having a transducer for speed now that GPS are accurate enough to get the instant speed, except for deducing the strenght of the
current (Speed over ground minus speed through water), which can also be deduced otherwise easily if you know a little your boat (SOG vs usual SOG in similar conditions + course deviation on the GPS).
So, GPS are almost there, but still, I can't find the tablet's GPS refresh rates, and I doubt any of them is above 1hz. Anybody? And what is the experience of instant speed recording with a 1hz?
3/ Last but not least, display. The goal is not to have 3 tablets (each one for a different information), and neither do I want to switch from one gadget app to another. It means that I need an app that would allow me to get all the information I need on a customizable screen (basically, all GPS information and map + wind, heading, and speed). I know that tons of app do part of it, but is there one that do it all? Which one? So far it seems that most people use
navionics for the
charts, and that
iNavX is the closest to what I'm asking for the apps. Anything else? Any good match to
iNavX in the android market?
That's about it, I tried to summarize what I know and what I'd like to know, feel free to add information, mainly about accuracy and display options (apps).
So far, my best guess setup is an iPad with iNavX and
Navionics AND a GPS enhancer for the speed records (as only the 3G able version of iPad has a GPS, and it is a 1hz). I hope that people here can help me find alternative setup, and tell me what were their experience with a tablet or another. Also, if anyone knows where to get the exact GPS chip information for the tablet market, I am interested.