Taking the venerable Tetris as inspiration, developers MRG have released Letris for Windows Phone. With letters falling down one at a time they avoid the use of the classic tetronimos (the four square block arrangement that makes a block in Tetris), and there's no requirement to choose letters next to each other (as you see in Wordament). But it's still a frantic mess of anagrams and too many blocks falling from the top of the screen. In other words, it's wonderful.
It's not perfect, but with three dictionaries on board (English, French, and Spanish), online high score tables comparing your gaming to other players that week, and with an all-time high score list, it covers a lot of the basics. I'll watch carefully for an updated version, but for now Letris has a lot of appeal to me with this first release.