I have upgraded the Collector for iOS to 10.3.1. I have a web map with feature services that I need to update. ArcGIS Online basic viewer can edit the features, as wel as the Collector on Android devices. On my iPAD the 'Submit' button is grayed out and I can't submit any record. Any clue??
Having the same issue with with Collector 10.3.9. All of the fields have been filled out with the correct data types. Only having this issue on select services. This problem is only happening on our IOS devices, android is working with the same services just fine.
The solution for me was to make sure that any auto-generating fields like Created By, Edited By, Edit date, have "Allow NULL Values" set to Yes. That seemed to do the trick.