Mule's Watch app for iPhone and iPad

What you can do:
With Mules Watch, you can bookmark a time zone region and keep track of the local time. If you want to check on an upcoming time change, you can also look up more detailed information such as whether the region observes daylight savings / summer time and when the next time change is going to occur.
You can look up time zone regions sorted by its 2 letter region code, the standard time offset, or the abbreviated time zone name.

Language Support:
The primary language of this app is English (US) with limited language support. The region names will be displayed according to the language set on your phone, and the rest of the text will be in English.

Inclusion/Non-inclusion of a Time Zone:
Any time zone not included in this app was not excluded for any criteria. What is included is every regional time zone that the app developer (myself) was able to find.