PROBLEM :

Device performance is poor and I cannot install new apps

SOLUTION :

If you can not install new apps on your phone and/or its performance is poor, it could be due to low memory. If you do not have additional internal memory on your device, you will not be able to install new apps. Additionally, your device may also be slow, begin freezing, or turn off. To free up enough memory, you should check the current internal memory and use the Device care feature regularly. Please check the steps below.

1. Sync and delete ephotos to clear up space. Turn on the Galley sync option and delete photos after the upload is complete. To do this, navigate to and open Gallery, and then tap More options (the three vertical dots). Tap the switch next to Sync with OneDrive to turn on the sync. Then, go back to the Gallery app and delete the pictures that were just backed up.
   
   
2. Use Device care to optimize your apps. Navigate to and open Settings, and then tap Device care. Tap Optimize now. This will delete residual files and clear out memory.
   
   
3. Uninstall unused apps. Navigate to the Apps screen on your device. Touch and hold the app you would like to uninstall. Tap Uninstall, and then tap Uninstall again. Repeat these steps for all of the apps you want to delete.

Now you should be able to install new apps on your phone. If you can not, continue to delete or uninstall unnecessary apps or files.