In my Lenovo Vibe K5 Note (3 GB, 32GB), even after I remove all apps from recent apps screen, still more than 2 GB RAM is shown as used. I have more than 2 GB of free space left.
A lot of apps runs in background , like google services ,sms push ,location provider, keyboard and so on and the whole Android system needs some of ram to properly run , if you still want to free up more ram then install lineage rom, .thats it ..
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