A free program for Android, by Rolling Coders.
To keep your phone from lagging, you should perform some cleaning it with whenever it needs to. There are a lot of cleaning and boosting apps out there and Pro cleaner 2019 HD is one of them.
With this tool, you can scan your mobile phone to see if there are any duplicates, junks, or caches hiding somewhere in your device. Those things make your phone lag or worse, make it prone to viruses.
This free up your mobile storage so you can still keep or save more photos or files. In addition, it also cleans your RAM and make your device optimized.