Re: Is this the review of a camera or a phone?
Having an app that performs a service using the system API means that app may screw up.
And? How is that going to make the system unstable? If the system is not providing APIs for this then it's going to be tightly coupled and much more difficult to maintain than one using an API.
This would require that they shoe-horn every cloud service into the current API
No, alternative services would have to provide code that fulfils the API. That is the whole point of an API.
Alternatively, they would have to add to the API to cover the cases that could not be driven within the current API.