Available everywhere without installing anything, and I don't need to worry about file formats. With Google Drive I also appreciate that I can write custom func

Available everywhere without installing anything, and I don't need to worry about file formats. With Google Drive I also appreciate that I can write custom functions using javascript which I already know, rather than learn some obscure language. I tried gnumeric just now and the crappy looking toolbar and the poor autocomplete experience for formula functions was enough to put me off.