You can select which type of calls to save and the calendar to save calls in.
Differences from "Call Log Calendar" paid version:
1. automatic saving is not available
2. gps/network location for the calls are not available
Purchase full version to have those extra functionalities and support developer.
Known issues (important):
A) There are a few reports of problems when using with Exchange calendars (please contact developer if you are able to cooperate with debugging this problem).
B) It is not possible to edit calendar events using HTC Sense 3.0 (reported by one user).
C) SMS saving is known to not work on most HTC phones. (multiple reports from users).
D) Syncing with Outlook provided by some phones is known to suddenly stop syncing and recovers after some time (multiple reports from users).