We've been using remote configuration or a few years in our mobile app. At first we ran a very simple custom implementation, and we later switched to a Saas that seemed to offer a more comprehensive solution. We've had many issues with it: the UI is terrible for large projects, there is no versioning of the configuration, no gestion of merge conflicts (when several devs are editing at the same time). Worse, the behaviour is not deterministic: if some segments overlap (our fault), it will serve either value at random (should not happen).

I was wondering if any of you had found a good solution? What are their pros and cons before we jump into it?