This looks like things probably started breaking for you with app version 4.1.3 released about 2 weeks ago.
Attempting to dig in, crash reports I’m seeing come from (ironically) our crash reporting tool. Previously we were using the Crashlytics framework in the app to be able to measure crashes. Version 4.1.3 updated that framework to the Firebaes/Crashlytics framework since Google is migrating and shutting down Crashlytics in a couple days from now.
It looks like it’s limited to iOS 10 where the issue happens which is why the crashes haven’t been more widespread. I’ll look in to see if there’s any adjustments that can be made or if the particular crash we’re seeing is a known issue to Google. If not, I’ll figure out some work around to keep it from crashing, though it’s hard to know if a workaround will work for sure since I don’t have an iOS 10 device and it doesn’t crash on the simulators.