Last week we used Collector for ArcGIS (version 10.3 on an iPad Air, AT&T) with our ArcGIS Online organization account for field data collection. We experienced loss of data, sometimes everything including the point feature itself, other times photo attachments. Since the collection was at or near urban areas and cellular signal strength was good in general, we didn't use offline mode and it was all done real time.
On day 2 of the collection there were a few instances with multi-photo points when the “submit” button was tapped it would take the App a while to process then a submission failed message would appear, offering two options – “Cancel” and “Retry”. Initially “Retry” was selected but the same failure message would appear again and again, so eventually the field crew clicked on “Cancel”. At that point the collected feature as well as attributes and photos were visible on the App, so they moved on to the next site.
When they were back at the hotel (on Wi-Fi) they realized 2 points they collected during the day were completely gone, and 3 other points were missing all the photo attachments. They also noticed 2 points from day 1 were completely gone (they couldn't recall with certainty whether the “failed to submit” message was encountered with them). Not knowing how to avoid more data loss, they went with paper and pen for the remaining of the collection and re-collection of the lost points.
Once they were back in the office we did more testing. While the cellular signal strength was at least 3 bars out of 5, it was pretty easy to duplicate the issue by taking more than 3 or 4 photos and submit.
Here are our questions:
Is our instinct correct that our issue could be caused by the data volume submitted each time?
We like the convenience and ease of set up with this solution. However based on our first project the reliability is too low for serious application. I can’t imagine we are the only one needing multiple photos for each collected features. Has data loss been a common issue?
What is everyone else doing to make this solution work? I assume the reliability will improve if each submission is limited to one photo, but it’s such an interruption to the workflow.
When collecting in “online mode”, is there a way to explicitly back up the data collected onto the mobile device?
We are thinking maybe offline mode can be more reliable and will do some tests. But from experience, will syncing (Wi-Fi or cellular) be problematic if a collected feature contains a large number of photo attachments?
Any recommendation on more reliable solutions that works with ArcGIS Online?
How about complete on device Apps?
Update: after talking with an ESRI technical support back and forth, he started being able to duplicate the problem on his end, and has registered this issue as a bug. We did perform more tests of our own. It seems that one photo per submission/update is problem free, so while on cellular only if multi photos are needed for a collection point you'll have to update after each photo is taken. Offline mode seems to be working fine.