Best Anchor App

Learn something new everyday. Never new there was an app for this. Sure could have used this a couple of weeks ago. Looking forward to the responses.
 
I've tried them all and I don't find them particularly useful for my needs. You're phone's GPS is pretty accurate but not down to the inch. All of the apps that I used either gave me a false alarm due to sway or, if I did drag, it wouldn't notice until I moved 5-10 feet. If you're in a tight anchorage or trying to keep from dragging into shore then a several feet of error is a lot.
 
Blueone said:
If it's not the best app ...it should win best name
Click to expand...

Yeah - but a couple of times people have seen the app on my phone and questioned what it was. I could see them nodding to themselves quietly when I was trying to explain it was a boating app...
 
I use a highly accurate External GPS with my iPad. It should alert within a few inches of going outside the boundary.
 
+1 on Drag Queen. It's worth it to have the Admiral find an app by that name on your phone.


Sent from my iPhone using Tapatalk
 
A typical GPS in a cell phone will have 3 to 5 meter accuracy best case. It can be out by as much as 10 to 15 meters and that accuracy can vary with atmospheric conditions. More important the precision will be that bad too. A good GNSS system that uses carrier phase will be better than 3 meters. You won't find one like that in a cell phone or even in a consumer marine GPS. One that uses RTK corrections can have accuracy down to the cm. For that kind of accuracy you will have to pay a subscription to get the RTK data.
 
All the Apps in the world wont help you if you don't have the proper anchor , the correct chain lead, or the correct scope .
Plus if your phone goes dead, what good is it?
 
FootballFan said:
Are inches that important with an anchor alarm?
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Westie said:
A typical GPS in a cell phone will have 3 to 5 meter accuracy best case. It can be out by as much as 10 to 15 meters and that accuracy can vary with atmospheric conditions. More important the precision will be that bad too...
Click to expand...

Bt Doctur said:
All the Apps in the world wont help you if you don't have the proper anchor , the correct chain lead, or the correct scope .
Plus if your phone goes dead, what good is it?
Click to expand...

I would say yes, inches are important with an anchor alarm. To clarify what I meant.... The GPS in most current cellphones is accurate within a foot or less which is phenomenal for navigating with apps like Navionics but the anchor alarms that I've tried couldn't tell the difference between my sway and dragging and they didn't detect dragging soon enough. Whenever I had a good hold the alarm would sound as I swayed around my radius giving me false positives. I personally want to know if I'm starting to slip even 6" so I can monitor and assess the situation to see if I need to reset the anchor. 6" is most likely not a huge deal but it could lead to several feet over an hour if not monitored and I want to know sooner than later especially in a tight anchorage. So, in my opinion, even though 12" accuracy is amazing...it's not good enough for me for an anchor alarm.

I did as Bt Doctur said, I learned how to properly set an anchor and I've never had an issue with dragging. I determine my bottom conditions and set the anchor accordingly.

As for the 3 to 5 meter accuracy.... I have to respectfully take issue with this. Current standalone cellphone GPS technology is way more accurate than 3-5 meters and even more accurate when you add cellular and wifi triangulation. Even if you're not connected to a wifi hotspot, simply having wifi enabled will increase your accuracy immensely. I stated above, most current cellphones within the last 1-2 years will be accurate to within a 1 foot or less. No, you won't get with a cm today but that day will come.

I verify my hold the old fashioned way.... once the anchor is set and the boat has settled I will sit or stand at the very tip of the bow and find 3 fixed reference points to triangulate my position then I make a mental note of my boats relative position to these points. Every so often I will recheck and if I haven't moved after 30 minutes, and especially haven't moved if conditions have changed, then I am confident of my hold and I can enjoy the time with my guests.
 
I verify my hold the old fashioned way.... once the anchor is set and the boat has settled I will sit or stand at the very tip of the bow and find 3 fixed reference points to triangulate my position then I make a mental note of my boats relative position to these points

Something not found in the "Book of Common Sense" but learned.
Also how many of you have the end of the anchor line secured to something inside the anchor locker?
How many have the shackle pin safety wired?
How many carry a second anchor with rope?
 
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Tonka Boater said:
I would say yes, inches are important with an anchor alarm. To clarify what I meant.... The GPS in most current cellphones is accurate within a foot or less which is phenomenal for navigating with apps like Navionics but the anchor alarms that I've tried couldn't tell the difference between my sway and dragging and they didn't detect dragging soon enough. Whenever I had a good hold the alarm would sound as I swayed around my radius giving me false positives. I personally want to know if I'm starting to slip even 6" so I can monitor and assess the situation to see if I need to reset the anchor. 6" is most likely not a huge deal but it could lead to several feet over an hour if not monitored and I want to know sooner than later especially in a tight anchorage. So, in my opinion, even though 12" accuracy is amazing...it's not good enough for me for an anchor alarm.

I did as Bt Doctur said, I learned how to properly set an anchor and I've never had an issue with dragging. I determine my bottom conditions and set the anchor accordingly.

As for the 3 to 5 meter accuracy.... I have to respectfully take issue with this. Current standalone cellphone GPS technology is way more accurate than 3-5 meters and even more accurate when you add cellular and wifi triangulation. Even if you're not connected to a wifi hotspot, simply having wifi enabled will increase your accuracy immensely. I stated above, most current cellphones within the last 1-2 years will be accurate to within a 1 foot or less. No, you won't get with a cm today but that day will come.

I verify my hold the old fashioned way.... once the anchor is set and the boat has settled I will sit or stand at the very tip of the bow and find 3 fixed reference points to triangulate my position then I make a mental note of my boats relative position to these points. Every so often I will recheck and if I haven't moved after 30 minutes, and especially haven't moved if conditions have changed, then I am confident of my hold and I can enjoy the time with my guests.
Click to expand...

Sorry but the current technology from the GPS chips in cell phones is not capable of better than 3 to 5 meters on a predictable basis. Yes sometimes they will give an accurate position but not to any confidence level. Current GNSS technology without RTK corrections is accurate to 1.5 meters. Changes in upper atmospheric conditions effect the pseudo ranges measured that directly effect the calculated solution. As well to calculate the pseudo ranges accurately a very stable clock source is required. High end GNSS receivers have a voltage controlled temperature compensated oscillator as a clock source. Having a stable and accurate clock source allows carrier phase measurements from L2 to be used. A cell phone GPS does not have this capability. With RTK corrections cm level accuracy is possible in high end GNSS receivers.
There are a number of single chip GPS receives available today that are low cost but the performance is limited as explained already. To get better accuracy a dedicated RF and digital ASIC are required along with a dedicated 100 MIPS ARM cortex A9 processor. There is a reason that the users that require high accuracy spend $1500 on GNSS receivers instead of buying the $3 to $5 cell phone GNSS chips.

Full disclosure : I work for the leading company in the world for GNSS receivers.
 
Bt Doctur said:
I verify my hold the old fashioned way.... once the anchor is set and the boat has settled I will sit or stand at the very tip of the bow and find 3 fixed reference points to triangulate my position then I make a mental note of my boats relative position to these points

Something not found in the "Book of Common Sense" but learned.
Also how many of you have the end of the anchor line secured to something inside the anchor locker?
How many have the shackle pin safety wired?
How many carry a second anchor with rope?
Click to expand...


Thats great (and I use the same technique for coving) but how's that work out for ya when your overnighting and the weather changes?
 
Am I missing something here?

We spend thousands of $$ for onboard navigation electronics, all of which incorporate anchor alarms in their systems. Do we really need to use an iphone/ipad for that purpose or is it over reliance on a technology that isn't as well suited for what we are trying to accomplish as systems we already have on the boat?

Due to the age of my boat and the fact that I like the original electronics package, I have 2 plotters and a separate GPS, from Furuno, B&G and Raymarine. All are either Differential or WAAS receivers and alert me to a move of 3-5 ft., which is good enough for my situation......If all I can get is accuracy to 15 meters with a phone based alarm, I'll pass.....my props would be in the sand before the iphone figured it out.
 
I just use my GPS chart plotter and turn on tracking. Then I zoom in enough to see the radius that I'm creating. After a few minutes the track creates a half-circle and just keeps retracing over itself. It doesn't offer an instantaneous alarm for an overnight or in adverse conditions, but it offers excellent piece of mind in casual anchoring situations. And if I use my GPS transmitter with Navionics on my iPad, then I can keep it down in the cabin with me and glance over every few minutes.
 
Westie said:
Sorry but the current technology from the GPS chips in cell phones is not capable of better than 3 to 5 meters on a predictable basis. Yes sometimes they will give an accurate position but not to any confidence level.....

Full disclosure : I work for the leading company in the world for GNSS receivers.
Click to expand...

Not to beat a dead horse....

I don't dispute the accuracy of a high-end GNSS chip vs. a smart phone chip. I will argue the predictability and accuracy though....

The iPhone 5 has 10' accuracy within seconds and it's even more accurate with wifi and cellular enabled...the iPhone 6 & 6+ are even more accurate. As you travel around, your phone will by default keep a log of all your positions and the positions of hotspots and cell towers that it passes and it builds a massive internal database. It combines this data with data from the millions of other users to give you near pinpoint accuracy within seconds (within feet). The phone's GPS becomes even more accurate and powerful when paired with great apps such as Navionics, Google Maps, etc. that also have their own massive stores of location data...pair the app data with the device data and you get predictable and reliable GPS information from just about anywhere. The advantage that cell phones have is the power of numbers....billions of data points gathered by millions and millions of users. This is why dedicated GPS devices require high-end chips....they don't have the massive caches of user-generated data the phone makers do.

If you are in the middle of the ocean with nothing but a quality phone it's possible to get better than 10' if you also have a quality app with built-in data....if you're stuck in the middle of the ocean though, 10' is good enough.
 
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