This paper describes Test Editor, an authoring tool for building both mobile adaptable tests and web-based adaptive or classic tests. This tool facilitates the development and maintenance of different types of XML-based multiple-choice tests for using in web-based education systems and wireless devices. We have integrated Test Editor into the AHA! system, but it can be used in other web-based systems as well. We have also created several test execution engines in Java language in order to be executed in different devices such as PC and mobile phones. In order to test them, we have carried out two experiments with students to determine the usefulness of adaptive tests and mobile tests.