A new setting for Ionic app - sorting of posts from Wordpress

I want to make an app based on Ionic framework with rest api from Wordpress. I need to make a new setting. When user will touch setting, must appear a input box, where user will write for example postal code . Post publicated on Wordpress will have in tags writes postal code. And when user will input the postal code in setting, he must see all posts with these tag, with this postal code. Will be a type of sorting. I will have category on this app, we get them from Wordpress. I want after sorting the app, user must get the posts included in categories. not only a list of result. I based my project from zhis [login to view URL]