Recently I have developed a Drag and drop dynamic filter which generates JSON. you can integrate into any Application no matter it is the iOS app, Android App or Web App.
You just need to integrate this code into iFrame or Web view so that user will build his/her desire filter option using very easy drag and drop functionality. And at the end, you will get JSON which you need to pass to the server. And the server will parse this JSON and apply DB query based on JSON object. and the server will return the JSON string.
So bye-bye to traditional fix filter. With my filter user have full flexibility to build his/her desire filter and very user-friendly.
Soon I will release its downloadable version with proper documentation. As of now please play with this and let me know in the comment section what new feature you want to see in this to make it more user-friendly with more productive.