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Imagery Explorer

The Offline Maps tab is where you find and download satellite imagery. The Imagery Explorer is the map-based way to browse it -- drag around, tap a dot, and see what imagery exists for that patch of water.

The Offline Maps tab

Two buttons at the top switch between Map Overlays (satellite imagery and district overlays) and NOAA Charts (see NOAA ENC Charts).

Below that is a Search bar and an ℹ️ button that explains the screen.

On the Map Overlays side, the page is a stack of sections:

Section What's in it
Recommended Downloads Imagery you probably want but don't have yet
Imagery Explorer The zone-dot map described below
Request a New Area Ask for imagery somewhere we don't cover -- see Request a New Area
Recently Added Newest imagery in the catalog, as a side-scrolling strip
District groups Everything else, grouped by region and district

Sections with something new carry an orange count badge.

Splits into two lists:

  • The first is imagery for your selected area. If there isn't any new, it says No new maps for your area.
  • Images at your location -- imagery whose coverage includes where your GPS says you are right now.

The Imagery Explorer

Tap the Imagery Explorer header to open it. The badge shows how many new images it's found, e.g. "12 new".

Inside is a small map with a dot for each imagery zone. The hint under it reads: Drag and pinch to explore -- tap a dot to browse that area's imagery.

Filter chips

Four chips above the map narrow which zones show:

Chip Shows
All Every zone
Downloaded Only zones where you already have imagery
Available Only zones with imagery you haven't downloaded
New Only zones with imagery you haven't seen yet. The chip shows a count, e.g. New (12)

If nothing matches, a badge appears over the map saying so.

Browsing a zone

Tap a dot and a strip of cards appears below the map. Each card shows:

  • A preview image of the imagery
  • A gold NEW tag if you haven't seen this one before
  • A green ✓ in the corner if you already have it downloaded
  • The image name and the date it was taken

Tap a card to select it. An action row appears with the name, some detail, and two buttons:

Button What it does
Download Starts the download straight away. The button changes to "Downloading…" and a toast confirms it started.
Details Opens the full detail view for that image and marks it as seen.

A See all link opens the complete list for that zone, newest first, regardless of which chip is active.

Previews load as you scroll

Preview thumbnails are fetched on demand. A card showing a ⟳ is still fetching its preview.

District groups

Below the explorer, the whole catalog is grouped by region, then by district, then by individual map. Each level is an expander -- tap to open it.

Each district header shows how many of its maps are switched on out of the total, and opens to show Downloaded: and Not Downloaded: counts.

Every individual map has a switch that controls whether it loads on the navigation map.

View All Maps

Each district has a View All Maps button that opens the All Maps popup -- every map layer for that district in one scrolling list.

The popup's own ℹ️ explains what you're looking at:

  • Download Button -- download maps you don't have yet (orange button)
  • ✓ Downloaded -- green checkmark shows maps you already have
  • Map Size -- file size displayed for maps not yet downloaded
  • Tide Height -- reference tide level used for chart creation
  • Preview Images -- small thumbnails show what each map looks like
  • Sort Order -- downloaded maps appear first, then sorted alphabetically

Tap the ⟳ Tap to download preview placeholder on a row to pull down its thumbnail.

Searching

Type in the Search bar to filter the list by name. On the NOAA Charts tab the same bar filters regions instead.

Filtering and sorting

The Filter button in the toolbar opens Filter Maps:

Control Options
Sort By Date (newest) or Name
District Pick a single district
Time Period Last 6 Months, Last Year, Last 2 Years, Last 5 Years
Custom Date Range From Date and To Date pickers
Tide Height Range Min and Max sliders, with the available range shown underneath

Apply Filters puts them into effect; Reset Filters clears them.

Tide height is the useful filter

Imagery of the same ground at different tide heights shows you different channels and bars. Filtering by tide height is how you find the low-water shot of a particular bay.

The Recommended button in the toolbar opens Recommended Maps -- pre-built sets of layers with priorities and transparency already configured. Tap Apply on a set to configure it.

If you have nothing downloaded at all, the page shows No Maps Downloaded with two buttons: Try Recommended Maps and Browse All Maps.

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