I was looking for an anchor alarm app. There are many choices out there. I'm curious which ones people like? Is there e one or two that are better / more cost effective than others? What are your thoughts?
What is your favorite anchor alarm app
- Thread starter SV Temenos
- Start date
Assuming you mean "mobile app", I kind of have a (personal) problem with anchor alarm apps, in general.
Disclaimer: I've made a living in software development, so I am hyper-aware of some technical issues that, for most people, most of the time, won't be a problem. So, to some extent, it is probably over-concern.
The problems are these:
First, phone batteries die on boats, disproportionately. That is, at least for us, we are out of our normal routine about when/how we charge. So, this it seems that one of our phones is always running low. That isn't really a technical issue as much as simply a discipline issue. But, for us, it is a consideration. Of course, it is reasonable to say that, if you are going to bother setting an alarm, you should probably also make sure your phone is charged and plugged in. Agreed.
But, the more insidious issue is that phones manage their own battery usage by putting processes to sleep that it feels are not actively needed. When you develop an app, you can specifically declare that the app needs to stay "alive" in the background and should be immune to the system putting it to sleep. And, most of the time that works as intended.
But, this behavior can vary across devices and operating systems, depending on a number of factors. It can be 100% reliable on most devices, but there is invariably some edge case where it silently goes to sleep on certain devices. And, it can be reliable on a given device except under certain situations (like in a power-saving mode) so that it works perfectly ... until it doesn't. It will always fail silently.
Even an app that reviews very well for high reliability - that isn't super helpful. It isn't hard to make an app that works most of the time for most people. It is nearly impossible to make one that is completely reliable. The problem with positive experiences is the fact that most of the time, the anchor doesn't drag. So, a user doesn't always know there is a problem with the app going to sleep - especially if it only happens under certain conditions.
So, knowing this, an anchor alarm app doesn't help me sleep at night. Knowing that it will "probably" alert me isn't the comfort I need.
For me to not wake up at every motion or sound, I need dedicated hardware whose job it is to do that one task reliably. I developed a device that does just that. It monitors for anchor drift - that's it. It has its own GPS receiver and is wired independently, with its own battery backup. If power fails, it alerts that it is on battery backup. If the battery runs low, it alerts to that.
For convenience, I made a mobile app that we can use to manage the device, but once set, the device works independently. For additional peace of mind, the app periodically pings the device and, if it does not get a response, the app alerts to that fact (suggesting the device is offline, for some reason).
I set this up on my previous boat, but still haven't bothered on the new boat. Somehow, despite my anchoring over-cautiousness, I just never think to set the anchor position when I drop it. The anchor alarm is always an afterthought. I've considered installing a button in the cockpit right next to the windlass switch, but haven't yet. So, it still requires me to get my phone out - something I never think to do in the moment.
Disclaimer: I've made a living in software development, so I am hyper-aware of some technical issues that, for most people, most of the time, won't be a problem. So, to some extent, it is probably over-concern.
The problems are these:
First, phone batteries die on boats, disproportionately. That is, at least for us, we are out of our normal routine about when/how we charge. So, this it seems that one of our phones is always running low. That isn't really a technical issue as much as simply a discipline issue. But, for us, it is a consideration. Of course, it is reasonable to say that, if you are going to bother setting an alarm, you should probably also make sure your phone is charged and plugged in. Agreed.
But, the more insidious issue is that phones manage their own battery usage by putting processes to sleep that it feels are not actively needed. When you develop an app, you can specifically declare that the app needs to stay "alive" in the background and should be immune to the system putting it to sleep. And, most of the time that works as intended.
But, this behavior can vary across devices and operating systems, depending on a number of factors. It can be 100% reliable on most devices, but there is invariably some edge case where it silently goes to sleep on certain devices. And, it can be reliable on a given device except under certain situations (like in a power-saving mode) so that it works perfectly ... until it doesn't. It will always fail silently.
Even an app that reviews very well for high reliability - that isn't super helpful. It isn't hard to make an app that works most of the time for most people. It is nearly impossible to make one that is completely reliable. The problem with positive experiences is the fact that most of the time, the anchor doesn't drag. So, a user doesn't always know there is a problem with the app going to sleep - especially if it only happens under certain conditions.
So, knowing this, an anchor alarm app doesn't help me sleep at night. Knowing that it will "probably" alert me isn't the comfort I need.
For me to not wake up at every motion or sound, I need dedicated hardware whose job it is to do that one task reliably. I developed a device that does just that. It monitors for anchor drift - that's it. It has its own GPS receiver and is wired independently, with its own battery backup. If power fails, it alerts that it is on battery backup. If the battery runs low, it alerts to that.
For convenience, I made a mobile app that we can use to manage the device, but once set, the device works independently. For additional peace of mind, the app periodically pings the device and, if it does not get a response, the app alerts to that fact (suggesting the device is offline, for some reason).
I set this up on my previous boat, but still haven't bothered on the new boat. Somehow, despite my anchoring over-cautiousness, I just never think to set the anchor position when I drop it. The anchor alarm is always an afterthought. I've considered installing a button in the cockpit right next to the windlass switch, but haven't yet. So, it still requires me to get my phone out - something I never think to do in the moment.
Thank you for the thoughtful response. Sorry yes I did mean mobile app. These days I forget there are other types 
. I'm a firmware engineer so I appreciate the points you brought up. Definitely things to consider.
. I'm a firmware engineer so I appreciate the points you brought up. Definitely things to consider.
An oversized anchor... i sleep well knowing I won't drag till the winds hit 50 kts
I've tried a few, they all fail when the phone's satellite reception degrades, which triggers the alarm....
Fully agree you probably need a real gps to make this reliable...
You can run signalk on the victron cerbo front a rpi.
I've tried a few, they all fail when the phone's satellite reception degrades, which triggers the alarm....
Fully agree you probably need a real gps to make this reliable...
You can run signalk on the victron cerbo front a rpi.
Long before electronics were in vogue, there were 2 ways of addressing an anchor holding station. An anchor watch is one and is still employed. The other is knowledge.. You need to know what the bottom consists of, you need to know ( if in a tidal zone) when high tide is and at what stage the tide is when you drop the hook and what scope is appropriate. And you need to know that the anchor is big enough for the weight of your boat and lastly you need to know the weather forecast....
I love the Aqua Map anchor alarm function. I use it locally on my phone and when I leave the boat use it on the iPad with remote display to my iPhone using the app’s “Anchorlink” feature. The app has a setting that allows you to prevent the iPad from sleeping while the app is open.
How I use it:
My iPad runs the app and connects to the onboard wifi, and is kept plugged-in to power when running the Aqua Map app with anchor alarm. It’s also connected via Bluetooth to a dedicated external Garmin Glo 2 GPS (because iPad internal GPS is not reliable and occasionally “sleeps”). I have a small inexpensive 4G router in the boat with SIM card (my Starlink service is paused, but I use that when cruising). Amazon.com
I receive any anchor alarms remotely if the app is running in background, and can check the status of the boat at will by opening the app on my phone.
I can also check the boat and surroundings visually using my onboard Reolink and Ring cameras that are inside and outside the boat, and would receive motion alerts if anyone were to board the boat (and talk with them via the camera).
How I use it:
My iPad runs the app and connects to the onboard wifi, and is kept plugged-in to power when running the Aqua Map app with anchor alarm. It’s also connected via Bluetooth to a dedicated external Garmin Glo 2 GPS (because iPad internal GPS is not reliable and occasionally “sleeps”). I have a small inexpensive 4G router in the boat with SIM card (my Starlink service is paused, but I use that when cruising). Amazon.com
I receive any anchor alarms remotely if the app is running in background, and can check the status of the boat at will by opening the app on my phone.
I can also check the boat and surroundings visually using my onboard Reolink and Ring cameras that are inside and outside the boat, and would receive motion alerts if anyone were to board the boat (and talk with them via the camera).
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