Is there an API to create order from external app?

[jinsley]

I'm building a react native (Expo) app that facilitates a service.

We are using Stripe SDK to do checkout for the service but I also want to add product add-ons like clothing.

Using Shopify would for product fulfillment would help.

Can we hook into any order API to send the product/cart data and customer data to Shopify to create an order?

I see there is an Android and iOS SDK but I don't think that can integrate into my current checkout workflow. I want the user to be able to pay for the service and product add-ons in one go.

https://shopify.dev/docs/storefronts/mobile

Would I need to look into the cart API to submit an order? 
https://shopify.dev/docs/storefronts/headless/building-with-the-storefront-api/cart/manage