I'm trying to integrate PayPal into a mobile App + server.
The App provides services (actual, physical services, performed by a partner) and we wanted to charge the client immediately after service completion.
This would require us to be able to request the user to provide us with some PayPal credentials and a way to use them whenever necessary to create the order, attach it to the client and capture the funds.
Basically, a checkout process similar to Uber.
I'm thinking the client "credentials" would be captured on the mobile Apps, with the actual checkout (order + capture) performed server-side using the client's "credential" upon service completion.
I confess I'm a bit lost, as it appears to me the checkout process can only be initiated by the client, and I fail to see how to attach an order to a client.