It is one of the most common problems in the Android operating system. Usually, when you open an app, you will see a black screen for a few seconds and then the app will crash with or without an error message. There are a few ways to fix this problem.

1. Most of the time, it might be a temporary loading issue. You just need to press the recent applications menu (usually the first left button) on your phone. Then you close the app that has this issue. Now open the app again. It may work normally.
2. Try a Hard reboot on your Android mobile. Press and hold down the "Home" and "Power" buttons at the same time for up to 10 seconds. Then, release the buttons and hold down the "Power" button until the screen turns on. Now you can try opening the app, it may work fine.
3. If none of the above is working, you can wait till your phone battery drains and it turns off automatically. After that put it to charge, and press the power button. It may work after this.
4. Finally, if you can't fix it with anything, you may need to uninstall the app and reinstall it. Android usually restores all settings after you re-install and log into the app. You can see if that fixes it.
5. Even in some rare cases, the re-install step also doesn't work. If that is your case, try installing older versions of the app. Good luck!

There are a few situations that may cause the load issue in mobile apps.

1. The Warsaw ZTM Bus Timetable app server may be down and that is causing the loading issue. Please try after a few minutes.
2. Your wifi / mobile data connection not working properly. Please check your data connection.
3. Too many users using the app at the same time. Please try after a few minutes.

If you have a login or account-related issue, please check the following steps.

1. The Warsaw ZTM Bus Timetable server may be down and that is causing the login/account issue. Please try logging in after a few minutes.
2. Your wifi / mobile data connection not working properly. Please check your data connection.
3. You may be trying with the wrong login credentials. Please confirm the details that you are entering are correct.
4. If you're using third-party social networks to log in such as Facebook, twitter, google, etc, check whether that service is working properly by visiting their official website.
5. Your account may be banned or deactivated for activities. Please read the error messages carefully.

1. Check your wifi/internet connection for connectivity.
2. Please check your mobile storage space. If you don't have enough space on your disk, the app can't be installed.
3. Verify that the app you're trying to install supports your Android version.

1. Please check your wifi / mobile data connection and verify that it is working properly. It may be down and stopping you from updating the Warsaw ZTM Bus Timetable app.
2. Confirm that you have enough storage space in your phone to download updates. If you don't have enough storage space, it can be blocking the app updates.

1. Check your phone volume if you have audio problems. Try to use headphones to find out whether it is an issue with your speakers or with the app.
2. If you've a video loading problem, please check your internet speed and wifi connectivity.

1. Go to your Apps->Warsaw ZTM Bus Timetable->Notifications and check whether notifications are enabled or not. If it is not enabled, please enable it.
2. Also if you don't get notification alert sounds, re-verify that you don't accidentally mute the app notification sounds.