As expected (read: Cydia: BiteSMS 8.1 available in final version), the best messaging application on iPhone jailbroken, BiteSMS, just added support for themes.
Expected by many users, they allow to modify the appearance of the application so that it matches for example with a theme Cydia previously installed (read: Jailbreak iOS 7: Top 10 of the best Cydia themes on iPhone).
To install a theme, simply go to the settings of BiteSMS then in Themes. Unfortunately, you can see that there is currently none available on this iOS 7 version. We will have to wait a few days to see the first creations from users.
Indeed, if you are a developer and have a certain artistic touch, BiteSMS provides documentation to create your own themes. You can find it (in English) at this address. It is then up to you to decide whether or not to offer your skins to users of the application.