hi everyone, today for the second time i got a notification in the bar saying "low on space- the phone's memory is about to be full". now the thing is that almost all of my apps run on the sd card. under setting>storage i saw that there are three things:external sd card which has plenty of space,internal phone storage which has plenty of space, and "device memory" which is almost full. my first instinct was to move pics and videos to the sd card but then i saw that they are under "internal phone storage" which has lots of free space. how do i free up this "device memory" ?? i'm clueless. for first aid i cleared all my whatsapp conversations and the notification about the low space is gone but i'm sure it will reappear. help someone?