I use CallTrack as well. It works very well and since it logs it on your google calendar, you can access the data (in case you need a particular phone number and you forgot your phone) from any PC through your gmail calendar. If you don't want to clutter your primary google calendar, just create a new one just for logging the calls (call it Call Log) as you can create and have multiple google calendars for a particular gmail account. You can also view the call logs through your stock calendar or "Business Calendar" app or "Agenda Widget" app by adding your Call Log calendar as another calendar whose events/content will be tracked.