You smartphone might get cluttered every now and then. It happens when there are so many apps that clog up the memory of your device.
If you'd like to learn more on how you can free up storage on your device, read this brief article:
https://conniebrittonshair.tumblr.com/post/618794832999202816/how-to-free-up-storage-space-on-your-android-phone
It won't take you much time to handle the issue and fix it quickly. Having a speedy device is an important part of enjoying android.