One of the tech sites I visit mentioned Kingsoft Office as being one of the better office suits for the Android platform.
I downloaded it from;
http://www.kingsoftstore.com/kingsoft-office-android (it is free), installed it as I normally do from my FTP server without any problems - I think it is also available from the play store.
It works without any problems that I can see on our rather old Android version - been using it for just over two weeks now.
The only complaint that I have, and it is personal preferences, is that it saves in microsoft formats rather than open doc formats.