I have written about Sternzeit by Sebastian Bothe before. It is an iPhone app for calculating stardates. It has just been updated to version 2.2. For some reason it requires the new iOS 6, which means that if you don't upgrade you cannot use it. (Hey, Sebastian, just because there's a new iOS does not mean that everyone needs or wants to upgrade!) New in this version, they months are all in German instead of English. There has been new text added, in need of spellcheck, explaining that the stardate is negative because it is based upon a future date. Then they give you another date that you can use instead, but it's also in the future, so either way you have to use a negative stardate. You can choose between 2323 and 2063. The former is the year from which The Next Generation counted their stardates. 2063 I guess was chosen because it was the year the movie, Star Trek: First Contact, was set in, although they do not explain why this would be the base for stardates a half-century earlier. So instead of -301275.75, you can have it say -50275.76. And, in addition to email, SMS and Twitter, you can share to Facebook or save to your camera roll, which creates an image of a postcard with the stardate printed on it.
And I can vouch that it has been updated to fit on my new iPhone 5's 10 cm screen!