Comment 7 for bug 1638769

I'll investigate why are you are getting that error with the tester app; it works fine on the phone.

Anyway, yes, the output you are getting from gdbus is expected, because you are not specifying the applicationId in your call to GetAccounts. You need to ship an .application file along with your app, and install it in /usr/share/accounts/applications/. See existing files there as examples. And have a quick look at https://developer.ubuntu.com/api/apps/qml/sdk-15.04/Ubuntu.OnlineAccounts.manifest-files/

Given that your project is rather generic and might not have prior knowledge on all the available account types it support, it might be a good idea for you to define a <service-type> (you could call it "ubuntu-storage-framework", for example) instead of listing all the individual services you support. But it's really up to you.