In the android app, when I’m browsing through a long list of words (such as those in http://www.memrise.com/course/266259/hsk-complete-traditional-characters/, which contains hundreds of words per level), I can click on an item to see details, most notably the Pinyin pronunciation of a word.
However, when I then return to the list, I always end up at the top. This is very annoying, because I have to swipe a lot to get back to where I was in the list. Since there is no scrollbar, there’s really no way to tell how far I have to go to get to my last position.