Another option would be Quick Zone
. It's basically a quick contact list to which you can add any of you contacts and specify different time zones for each and it will display everyone's local time. A small call button is also displayed to be able to initiate a call with a single touch.
There are two versions on the android app market: trial with a limit on the maximum number of contacts (3 currently) and paid (0.5 pounds currently) with no limits.
Here are the details:
free trial version and
full paid version.