Anchor Alarm is an easy to use application that lets you set and monitor your position relative to an anchor point. It shows your distance from the point, and bearing to the point. If your current position strays too far from that set point, an alert will sound. The main use for Anchor Alarm is for setting an anchor drag alarm when you are at anchor on a boat. But the app can also be used anytime you want to monitor how far you are from a starting point.
Using Anchor Alarm is very simple... just set your preferences, drop your anchor (or if you are not anchoring, get yourself to your starting point), and press the "Set Alarm" button. Pressing that button will record your current position as the "anchor position", and Anchor Alarm will begin monitoring.
If your current position changes such that you are farther away from the anchor point than the distance you set in preferences, Anchor Alarm will sound an alarm. If the current accuracy of the position information on the iPhone (ie. the GPS in the iPhone) exceeds the accuracy tolerance level you set in preferences, a different alarm will sound. If both the distance and accuracy levels are exceeded at the same time, the accuracy alarm will take precedence. You can choose to have a silent alarm for accuracy so that it won't wake you up if the GPS loses signal once in a while.
Anchor Alarm will remember your settings if you exit, for example to make a phone call or send an email. When you start Anchor Alarm, if you have an alarm set, it will begin on the Monitor tab and if not, it will start on the Set tab. Remember that if you restart Anchor Alarm, it may take a moment or two for the GPS accuracy to improve.
Anchor Alarm includes a setting that will keep your iPhone awake, so that the GPS will continue to have good position data. Since the GPS and CPU will both continue to be active, we recommend that if you run Anchor Alarm for an extended period, that you plug it into a charger or computer so that your iPhone's battery will not discharge.
Anchor Alarm requires iPhone software version 6.0 or later. Anchor Alarm does not need to be connected to the internet to function.
New in version 2.0: Anchor Alarm will send a notification when the alarm is triggered.
The app features a dark user interface so that if it wakes you up in the middle of the night, the dark colored interface won't ruin your night vision.