Android Client: Option to expand, collapse all folders at once
Nimbus Note's Android client (which I find very usable!) remembers the state of the folder tree even after closing the app, which is quite handy. On the other hand, if folders containing subfolders are not manually collapsed after expansion, the tree will get longer and longer. With a large folder tree, this quickly becomes confusing.
Therefore, it would be good if the Android client - like the web client and desktop client - offered the option to collapse or expand the entire folder tree with one tap.