System Concept: How AvNav Works
To operate and set up AvNav correctly in everyday use, it helps to understand the core idea behind the software. One secret to AvNav's performance lies in its separation of computing and display – the so-called client–server architecture.
With a traditional chart plotter or a standard smartphone app, everything happens on a single device. If it crashes or the battery dies, navigation stops and the anchor alarm goes silent. AvNav solves this problem by dividing the system into two components.
The heart of the system is the AvNav server. It runs in the background, often on a small, permanently installed minicomputer below deck. This server is the computational hub: it reads data from connected devices via a wide variety of interfaces – GPS antenna, wind data, AIS signals. It continuously calculates the route, writes logs and records, monitors the anchor alarm, and keeps the chart material at the ready.
The second component is the client – in other words, the device you hold in your hand to operate the system. Because the server handles all the computationally intensive work, the client no longer needs any navigation software of its own. A standard web browser (such as Safari, Chrome, or Firefox) is all you need. You connect to the WiFi network provided by the server and simply enter the web address of the AvNav server on your tablet or smartphone. Instantly you have the full nautical chart with instrument display right in front of you.
This concept offers unbeatable advantages in everyday life aboard. The most obvious is resilience: if the tablet in the cockpit becomes unusable due to rainwater or dies because of a dead battery, the system below deck simply keeps running. The route stays active, the autopilot continues on course, and the anchor watch remains sharp. At any moment you can pull out any other device – a smartphone, for example – connect to AvNav via the boat's own WiFi, and continue navigating exactly where the tablet left off. In addition, multiple crew members can access the system simultaneously with different devices – the skipper plans tomorrow's route at the chart table on a laptop, while the helmsman monitors the current heading on a tablet outside. Everyone sees the same data, always in sync.