Offline Mode

Construction sites are often in areas with poor or no mobile coverage. The SiteView mobile app is built for this reality — download map tiles before heading to site, capture points and measurements offline, and sync everything back to the server when connectivity returns.

How Offline Mode Works

The SiteView mobile app uses two local storage systems to enable offline operation:

• Tile caching (FMTC) — map tiles are stored on your device so the map renders without an internet connection
• Local database (drift/SQLite) — site data, captured points, and measurements are stored in a local SQLite database

Together, these systems let you view your sites on the map, capture new GPS points, take distance measurements, and review existing data — all without any network connection.

ℹ️ Did you know?

The app detects your connectivity status automatically. When you lose connection, an offline banner appears at the top of the screen. When connectivity returns, the banner disappears and syncing resumes in the background.

Downloading Maps for Offline Use

Before heading to a site with limited connectivity, download the map tiles you will need:

1. Navigate to the site or area on the map while connected to Wi-Fi
2. Open the Download for Offline option from the map menu
3. Select the area to download — draw a boundary or use the current visible region
4. Choose the zoom level range — higher zoom levels provide more detail but require more storage
5. Tap Download

The app downloads and caches all tiles within the selected area and zoom levels. A progress indicator shows the download status.

💡 Tip

Download tiles on Wi-Fi before leaving the office. A typical site area at zoom levels 14-18 is roughly 50-200 MB, depending on the area size. Higher zoom levels (19-20) are more detailed but can be significantly larger.

What Gets Cached

• Base map tiles — street, outdoor/topo, or satellite tiles for the selected area and zoom levels
• Orthophoto tiles — if you have viewed the orthophoto overlay while connected, those tiles are cached automatically

After downloading, the map renders from the local cache even with no internet connection.

Offline Data Access

When offline, the following data is available from the local SQLite database:

⚠️ Watch out!

Data created by other users or on the web app since your last sync will not be available offline. Always sync before heading to a remote site to ensure you have the latest data.

Capturing Points Offline

Point capture works exactly the same offline as online:

1. Enter capture mode on the site map
2. Your GPS receiver (phone or RTK) works independently of internet connectivity
3. Lock the position, add label, code, and notes
4. Save the point

The point is stored in the local database with a pending sync status. It will be uploaded to the server automatically when connectivity returns.

Sync Status Indicators

Each locally stored item has a sync status that you can see throughout the app:

A sync summary is available in Settings, showing the total number of pending and failed items across all sites.

Auto-Sync and Error Handling

When the app detects that connectivity has returned, it syncs automatically in the background. Pending points and measurements are uploaded to the server, new data is downloaded, and sync status indicators update as each item is processed. Sync is also triggered on app launch and when the app resumes from the background.

If a sync attempt fails due to a server error or transient network issue, the failed item is retried on the next sync cycle. Persistent failures appear in a failed sync items list in Settings, where you can manually retry individual items or retry all at once.

ℹ️ Did you know?

Failed syncs are rare and usually caused by brief connectivity interruptions during upload. The retry mechanism resolves most failures automatically. If an item consistently fails, check your connection and try a manual retry.

Smart Delete

Items that have been successfully synced to the server can be safely removed from the local database to free up storage. The app supports smart delete — it only allows deletion of synced items that have a confirmed server copy. Pending items cannot be deleted locally, preventing accidental data loss.

Storage Management

The SiteView app provides storage management tools in Settings. View tile cache size and local database size, clear cached tiles, and remove synced data to free storage. Monitor your cache size periodically — satellite and orthophoto tiles consume more storage than street map tiles.

Practical Tips

• Sync before leaving the office — let the app complete a full sync on Wi-Fi, then download tiles for your target area
• Check pending items before leaving site — glance at the sync status before heading back
• Clear old tile caches — free up storage by removing tiles for completed sites

What's Next?

• Settings — manage sync controls, cache size, and position source
• Point Capture — capture GPS points that sync automatically
• Installation & Setup — app setup and permissions