I want to let customers use our API in their mobile applications i.e ones that they develop.
I have never developed for mobile so don't know if having the clients secretAPI key stored in the app is secure. I am assuming they will be able to connect using SSL from the app so transmission will be secure.
From what I am reading online everywhere is suggesting using oAuth. But oAuth requires a sign in from the client's user which is not possible in this case as the clients users wont have an account with our service.