Whenever I run a few apps like QNeptunea, Web Browser and Music Player, I am told that my mobile is running out of memory. I think my data storage has enough free space (see attachment).

On the other hand, Drop Cache app tells me my Free memory is always 1/3 or less, even if there is nothing running and even if I free pagecache and inodes (but something must be running in background, I guess). Thus, if I open two or three apps my free memory would go near 0, causing some apps not to load at all.

There is also a "~$top" screenshot attached to this thread: https://www.dropbox.com/s/3yaoaj94ne...2012-20-10.png

What can I do about it?