Calindori 1.2 is out, the first stable release as a KDE application.
If you are running Linux on mobile you will probably find it useful. But you can also use it on desktop, since it is based on Kirigami, the KDE Framework for mobile and convergent desktop.
At the moment this functionality does not exist. It is still pending on a PIM backend that could be used in Plasma Mobile - there is ongoing discussion on this. Unfortunately, the Akonadi backend in its current state, can't be used on mobile. When such a backend comes to existence, Calindori will make use of it.
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