Snap! is a web-based application. It allows you to select from nearly 4000 cities.

Select a country then a city to display a representation of a sundial.

A red line then shows the current clock time at that location, with midnight at the top, and noon at the bottom.

If the sun is up, a blue line indicates the current sun time at that location, the sundial is lit, and its shadow is shown. Otherwise, the complete dial is shaded.

There may be a significant difference between the red and blue lines, especially if the city is currently using daylight saving / summer time, or if the city is very far east or west of the ideal centre of its timezone region.

A paid version (by subscription) is also available with several extra features. See the following:
1-Year Subscription
3-Year Subscription

You can discuss this app in our forum here.

Snap - The Sundial App - Copyright © 2011-13 Relative Data, Inc & Spot-On Sundials.

Extra Credits & Copyrights:

Zoneinfo time zone database is in the public domain
Geonames location database is licensed under a Creative Commons Attribution 3.0 License
VSOP87 astronomy database is in the public domain
Astronomy and time algorithms - Copyright © 2011-13 Relative Data, Inc.
Dial image - Copyright © 2000-2011 Piers Nicholson, Spot-On-Sundials
All Rights Reserved