GPS and Map

SpringEval uses the official Swiss coordinate system LV95 (EPSG:2056) for all geographic data. GPS input from your device (in WGS84) is automatically converted using the official Swisstopo approximation formula.

Recording Coordinates

In the Site Info screen, tap the GPS button next to the coordinates fields. The app will:

• Request location permission if not yet granted
• Acquire your current GPS position
• Convert WGS84 → LV95 automatically
• Fill in Easting (E), Northing (N), and Altitude fields

You can also enter coordinates manually in LV95 format (e.g. E: 2 720 000, N: 1 120 000).

> Tip: For best GPS accuracy, wait a few seconds after tapping the GPS button and make sure you are outdoors with a clear view of the sky.

Automatic Altitude Lookup

When you change the E and N coordinates manually — by typing them or by tapping the map — SpringEval queries the official Swisstopo elevation service and fills in the altitude for you:

• If the altitude field is empty, the value is filled in silently.
• If an altitude is already set, a confirmation dialog shows the proposed new height before it is applied.

A map tap triggers the lookup immediately; typed coordinates trigger it about 1.5 seconds after you stop typing. GPS capture is unaffected — the GPS reading already provides an altitude.

> The lookup requires an internet connection. Without one, simply enter the altitude by hand.

Coordinate Lock

Once a spring's position is final, you can protect it from accidental changes. To the right of the Coordinates section header is a lock icon with a Lock coordinates checkbox.

When the lock is active:

• The E, N and altitude fields become read-only
• The GPS button is disabled
• Tapping the map no longer moves the position

The lock is remembered per spring and new springs always start unlocked. Untick the checkbox to edit the coordinates again.

The Home Map View

The Map tab on the Home screen shows all your evaluation sites that have LV95 coordinates as coloured teardrop pins on a Swiss topographic map (SwissTopo WMTS tiles).

Marker colours

Each pin is coloured by the ÖWS (Ökologischer Wert der Quelle) classification:

• 🔵 Very good (Class I)
• 🟢 Good (Class II)
• 🟡 Moderate (Class III)
• 🟠 Poor (Class IV)
• 🔴 Very poor (Class V)
• ⚫ Not yet evaluated

You can switch between Structure and Fauna ÖWS scores in Settings (gear icon → Map colour source).

Map navigation

• Pinch to zoom, drag to pan
• When you have 2 or more sites, the map automatically fits all pins in view
• Single site → zoom level 13
• No sites → overview of Switzerland

Map Display Settings

In Settings (gear icon on the Home screen):

• Map colour source: choose whether pin colours reflect the Structure or Fauna ÖWS classification
• Both classifications are always shown on each site card in the list view

Offline Map Usage

The SwissTopo map tiles require an internet connection to load. If you are offline, previously cached tiles may still be visible depending on your device's cache. Your site data and coordinates are always available offline regardless of map tile availability.