In the reference guide [https://docs.particle.io/reference/ios/], I can only access an account which holds the devices, which then will allow me to invoke a function. Is it possible or only invoke a function without logging in, but using the Particle Access Token or Device ID?
I think, logging in with credentials is merely to get an accesstoken, which is then used for further communication. As such, you should be able to inject an accesstoken yourself, as is described in the reference section: “injectSessionAccessToken”. Give that a shot? (No guarantees, I’m not an iOS developer, but that’s how I do it in javascript as well.)