Marine chart plotter · Android
NavView is a chart plotter for passage planning and situational awareness. A real IHO S-57 / S-52 engine — not a pre-styled tile viewer — under an instrument panel built to be read at the helm.
The engine
Most mobile plotters ship charts as pre-styled raster or vector tiles baked on someone else's server. NavView carries an OpenCPN-lineage S-52 presentation library and renders official S-57 cells on the device, at read time.
Capabilities
Nine surfaces you will use on passage. Each opens as a drawer over the plotter, so the chart never leaves the screen.
Official S-57 cells with S-52 symbology, plus OSENC, encrypted .nav packs, BSB/KAP, GeoTIFF, MBTiles and PMTiles vector tiles. Import a folder, a ZIP or a single file.
Library, Store and My Charts. Browse packs by coverage polygon, edition and cell count, then keep them on the device — no online open checks once a pack is down.
Navigation, Sailing and Motor pages. Pin compass, wind, depth and speed gauges anywhere on the plotter, then long-press to move, resize or swap them.
Build multi-leg routes on the chart, rhumb line or great circle. Passage face with ETA, TTG and leg breakdown; XTE corridor rails; per-waypoint arrival radius and planned speed.
329 bundled markicons in twelve categories. Track recording ported faithfully from OpenCPN's commit algorithm, with daily rotation and jump filtering. Douglas–Peucker reduction on demand, off the main thread.
Two independent watch points, each with its own ring. Drift mode alarms when you leave the swing fence; keep-out mode alarms when you enter. Hold MOB to raise a man-overboard mark.
Class A and B over 0183 VDM/VDO or seven NMEA 2000 PGNs. Threat and Clear sections, CPA and TCPA cues, true vessel dimensions at close zoom, lost-target handling.
GRIB overlay for the live forecast — wind, pressure, waves, current and more.
Eight input types, six output sinks, per-category forwarding and a source arbiter. Your phone becomes the multiplexer — it can feed OpenCPN as easily as it reads your instruments.
Anchor watch
A stern anchor, a shore line, a rock you want to stay off — each gets its own ring. Watch 1 can alarm when you leave your swing fence while Watch 2 alarms if you drift into a keep-out ring.
Connections
NavView is not only a consumer of boat data. It takes seven kinds of input, arbitrates between competing GPS sources, and rebroadcasts filtered NMEA to anything else on board — including OpenCPN on a laptop at the chart table.
Fix quality
Most plotters show you a position. NavView shows you how much to trust it — GNSS quality is a first-class instrument, not a hidden diagnostic.
Built for the helm
The interface follows one rule above the rest: it behaves like a marine multi-function display, not like an app. Nothing slides, fades or reflows while you are trying to read a number off it.
Columns are width-locked and slots are reserved even when empty, so a timestamp never shifts mid-scroll. Panels snap open. Only needles and glyphs animate.
44 px is the floor for anything you press. Destructive actions arm before they fire — stopping a recording is two taps, and the arm window closes itself after three seconds.
Condensed tabular numerals, uppercase micro labels, hairline rules and recessed wells. Labels never dim, because a label you cannot read is a value you cannot use.
Day, Dusk, Night, Dark and Paper repaint the chart for the light you are in. The app's own chrome stays dark throughout, so nothing flares at you on a night watch.
When a datum is missing you get one blank mark — an em dash — never the last value it happened to see. The scale bar draws nothing rather than a wrong-length bar.
A 39-topic manual ships in the app and is candid about limits: CPA cues are visual, there is no depth sounder alarm, draft is stored for reference. Fewer surprises at 0300.
Free, and quiet about you
Every feature in the app is unlocked. There is no premium tier, no subscription and no sign-in. Charts are the only thing that costs money, and US waters are free.
Get started
NavView is free on Google Play. Bring your own charts, or start with the free US coverage in the store.
Requires Android 8.0 or later on a 64-bit ARM device. Phone and tablet.