The automated end-to-end testing of applications allows to detect regressions early during the development and provide solid foundation for future modifications. However, implementation of such tests for mobile applications on Sailfish OS platform is related to some issues, especially when the application contain custom QML components written in C++. In the paper the authors present a method to resolve these issues, including two approaches to provide custom QML types in the testing environment and corresponding architectural considerations that make the code testable. The authors also describe an open source tool for running end-to-end tests on the integration server that supports the described method and supplements tooling of the Sailfish OS SDK.