Custom woocommerce APIs for mobile applications

Hello,

I have a requirement where I want to develop mobile app for my woo-commerce store.

I know about WC REST APIs. But I think there are some functionalities which can not be done by WC REST APIs, so please read my below list and suggest what can I do in different steps.

I have created a read only Key for a wordpress user having ‘customer’ role.

1. Show Categories, Show Products on mobile home screen – I can retrieve list of categories & products via API key generated as mentioned above.
2. when user add items to the cart, I can manage that offline on mobile device.
3. When customer want to place an order, I will need customer login/registration. I see there is OAuth mechanism but may be customer is not already registered with WC and I don’t want to show that we are running WordPress/Woocommerce. So How can I register/login using REST API and place an order on behalf of customer(actually customer is placing the order)?
4. also then I would like to show customer orders list and detail in my account section of mobile application.

Can someone let me know how can I do this? Can WC Rest API can be useful in this case? if Yes, how?