What Can Go Wrong?
When you are in the early stages of a software project, you try to take all possible issues into account. Yet things often go wrong.
We have observed the following incidents and problem areas during testing and quality assurance of mobile solutions across numerous projects (note that neither the categorization nor the examples of pitfalls should be considered exhaustive in any way).
What most of them have in common is that they were discovered outside of structured, requirements-based testing (primarily during exploratory, experience-based testing), using various mobile-specific testing techniques.
Error Areas and Pitfalls
Below, we have categorized the pitfalls according to where they were observed. Not all items are self-explanatory, but if you are involved in a mobile project, you may recognize some of them.
Process and Planning
- UI and functionality are not tested on sufficiently representative test configurations
- Edits in CMS systems often “break” the responsive design
- App version control – are you even testing the correct version?
Functionality
- Control elements do not work across all configurations
- Portrait / Landscape scenarios (scrollable menus, layout issues, page reinitialization, etc.)
- Missing functionality compared to web solutions (mouse-over, drag & drop, cache issues, control elements)
- Animations (videos) used as background in the app that unintentionally block screen lock
- Videos and other media files often do not behave as expected (do not pause during calls, etc.)
- Improper handling of automatic screen lock
- Language switching – is it handled correctly in the app?
- Dark mode – is it supported in the app?
- Accessibility features – are they supported in the app?
Technology and Performance
- Inconsistent implementation/performance – test in parallel across platforms to detect such issues
- Insufficient handling of missing/poor network connectivity (connectivity scenarios)
- Too many API calls, which in production will overload the backend disproportionately
- Handling of app backgrounding (sensitive screenshots of app screens, robustness issues)
- Coexistence with other apps using technologies such as Bluetooth (BT), BLE, NFC, etc.
Usability
- Input methods – incorrect keyboards, lack of input field focus/centering, or hidden input fields
- Difficulty tapping links, checkboxes, dropdown lists, date pickers, close buttons (“X”), etc.
- Navigation within the app. Does it follow the platform’s Look & Feel? Can users unintentionally navigate back using Android’s Back key? Are back links missing in iOS?
- Overlapping UI elements (buttons, text, checkboxes overlapping each other), e.g., caused by accessibility or zoom settings
- Poor perceived performance (subjectively long response times for user interactions)
- Missing notifications
- Too many notifications, often not descriptive
Installation and Updates
- App permissions – does the app handle permissions correctly?
- Uninstallation scenarios – is all data removed?
- OTA update scenarios and data migration – does the update succeed? Is all data preserved?
Last but not least: Things that used to work but suddenly no longer do. Do not compromise on a sensible and comprehensive regression testing strategy!