Waldo is a mobile app testing platform that allows developers to evaluate their mobile apps and remove bugs. The platform runs in the background processes when developers test their apps to make sure that they always produce bug-free apps. Waldo is a browser-based solution that records every screen and logic, enabling users to learn the structure of their app. Users can easily launch error-free updates of their existing apps by replaying their tests against the new versions automatically. In case the test failed, the platform informs developers what and where errors came from so they can fix the issue in an instant. Moreover, users can functionalise individual tests by setting up a differential criterion at each step of the testing process and make sure that the UI gets displayed in the exact way it has been designed. A powerful dashboard within the platform allows developers to streamline the required test results, monitor problems and leverage app crash reports to find the right solution.