I want to create a shopify app for manage shipping method on checkout page. I provide admin panel to store owner for create pickup locations. then I will create two shipping methods like same day delivery and next day delivery. I will check customer shipping address and based on shipping address I check which method display on checkout page.
But I do not know how to update checkout shipping method according to customer address by api.
please explain is it possible or not? because many other third party apps are doing this feature.