ExReg offers you a quick and easy interface to test your regular expression; its strength and in the iOS action extension.
The action extension can be activated in all the apps where you can select texts. Once activated you can run your regular expression to extract a content or to replace it with something else. The result will be copied to the clipboard ready for use.
In the app you can register your regular expression for quick use either in the action or, if you have it, in Msg ExReg.
Sorry for English (thanks Google Translate) and if you want to help me to evolve the app write me with tips and ideas; thank you!