That's because of some temporary files such as cookie files, cache etc. So there are some apps that will reduce lagging of your device. There are some tips that you can boost the speed of your device without any app.
Also Read: How to Disable/stop receiving Facebook apps and games requests from friends
1) Clean Master Phone Boost
This is the best app for cleaning unnecessary files from your device and it helps you to close some background apps. You can manage the list of cache files, I mean you can ignore some files to keep them, such as offline maps, offline languages pack.
The app contains Antivirus app inside so it will keep your device secure.
You can add some gadgets to your home screen and clean junk files or close background apps just with one tap.
Get Clean Master Phone Boost from Play Store for free.
2) CCleaner for Android
This app is a famous one, because of its PC version. This app works smart and easy. It will clean your Android device from unnecessary files just with few clicks. It will free up your device storage, track your RAM and internal storage space, it is compact and efficient with low memory and CPU usage. So if you want a fast device and more storage then you should try this app.
Get CCleaner for Android from Play Store for free.
3) DU Speed Booster (Cleaner)
This app will clean your device junk files and close some background apps to speed up your device. It also can boost games, to open them faster. It has integrated antivirus program inside. Which means it will keep your device clean, fast and safe. Smart scan and customizing option for junk files removing.
Get DU Speed Booster (Cleaner) from Play Store for free.
4) 360 Security - Antivirus FREE
This app is more concentrated on the security of the device. But it has the features to clean junk file and close background apps.
Also, there is a feature to block unwanted phone calls and SMS. So it will keep your device very secure.
Get 360 Security - Antivirus FREE from Play Store for free.
There is a list of some apps that you will find useful too.
Get 1Tap Cleaner (Cache, History) from Play Store for free.
Get Assistant for Android from Play Store for free.
I hope you get back the speed of your device and these apps will help you to free up some space.