I was hoping I was just missing something and there was a clean way to basically reach out from a mobile device and update my Calibre metadata.
I'd say the "Later" step probably isn't worthwhile, that the "Even later" would be a better use of limited resources since as you state, expectations (and bugs) would escalate. It does seem like a logical thing to expect from the user side.
I was a systems analyst in a former life, but I really don't know much about developing using current operating systems. But to do your "even later" scenario, it seems that you are heading more toward something such as Evernote, which is another program that I love. They have apps for every mobile device and every type of operating system. You can modify most all of the data from any of them, although they have a lot fewer actual data fields to deal with. However the Evernote data resides in the cloud instead of on an individual PC. Is that the way Calibre would need to head in order to allow for a similar interaction from various places/devices without all sorts of data issues? There must be some critical ability in being able to control cloud data differently. Or maybe they just have a slew of developers sitting around working on it.
I am so very happy with Calibre and CC, and I will happily use one workaround or another to keep track of what I read for the time being.
Thanks so much for taking the time to respond in such detail.