Sounds like you need to simplify. It sounds extreme but what about rebuilding your application in a proven, stable and maintainable web framework, then deploying to the native platforms using something like Cordova. That way, you only have one codebase to maintain.

Also, be careful about baying to your customers every whim. They don't always know best. Keep your product true to its roots (the reason they came to you in the first place). Provide rational and reasonable explanations why you won't be implementing their request. If they have a really good idea then say that you'll put it on the roadmap.