Use sentry.io?
Sentry.io is a service that helps tracking problems experienced by users. Basically, any uncaught exception will be send to sentry and then we can get information about the problems people are experiencing. Obviously this has privacy implications and there might be other reasons why it could be objected to. On the other hand, it would be very useful to get automatic feedback, since users tend to just abandon software that doesn't work instead of telling us about it.
In any case, probably something for later in the life-cycle of climix.