Why field apps go blank in a dead zone
Most field apps fetch map tiles from a commercial service as you pan and fetch your leads from a server as you move. Both are per-request arrangements with nothing stored locally, so when the connection drops there is no fallback to degrade to. The white rectangle is not a bug; it is the design working as intended without a network.
The per-request model
The app asks for a square of map, the service bills for it, the square appears. It is a good arrangement commercially and it means the device holds nothing. Lose the connection and there is nothing to fall back on.
Degraded modes get built badly
Apps that do attempt an offline mode usually build a separate reduced path, which is rarely exercised and therefore rarely correct. A design where offline and online are the same code path has no separate mode to get wrong.
What a working design looks like
Map data stored on the device and read locally either way, IDs generated on the phone so new records do not need a server, and a queue that replays writes in order with the original timestamps.
Common questions
- Why does my sales app show a blank map?
- Because it fetches map tiles per request and holds nothing locally. With no connection there is nothing to draw.
- Is offline mode hard to build?
- The hard part is not having a separate offline mode at all. A degraded second code path is what tends to be wrong when it is finally needed.
- Do any competitors handle this?
- Support varies and the complaint is common across the category. Test it with aeroplane mode before a season rather than after.
More on working offline
Dead zones, saved maps and field reliability — the wedge, and the thing reps complain about most.