Cleaning up the junk data on phone

[Gnaswer]

There is a lot of junk data on Android phone, And it seriously affects the operation of Android phone , i have tried to delete them on phone  , but it's harder than I thought, the deleted data can be found on other phone device , 

Now, i want to know if i can delete them form my phone and won't hurt other phone data .

Any suggestions ?

[nukecad]

CCleaner for Android does the job for me. There other junk cleaners for Android out there.

https://www.piriform.com/ccleaner-android

It sounds though as if you have 2 phones that are synced?

You may need to unsync them, clean each, resync them.