WordPop is a great game for Palm OS. It is a word game similar to Boggle, but because you can turn the playing field and slide the letter tiles around, it also has Tetris-like elements to it. WordPop has a lot of potential for replayability. My personal highest scoring words so far are WHEREVER, JALOPIES and FLAPPING for 190 points each, and QUILTERS and TAXATIONS for 180 points each.
Here is my strategy guide to the game.
Start of board: Trouble Letters: each time you get a new board full of letters, start by looking for the "difficult" letters Q, J, X, Y and Z. Note the positions of these letters (if they appear), because they can cause trouble for you later if you can't find words for them early on. Your goal should be to get rid of these letters soon. They can be very good because they are high-scoring, but you should use them up early in the board while you still have a lot of options. Remember not to use up all the U's while you still have a Q. Some boards have a Q and only one U.
Start of board: High Scoring Words: the other thing to do at the beginning of a board is to try to find high-scoring 7+ letter words. You may find one that can be spelled on the very first move. You may also find a "close call," a 7+ letter word that you can almost spell, but some letters are out of position. Make a small word that shifts the tiles so that you can make your big word on move 2.
Middle game: vowel/consonant ratio: in the middle game of each board, pay attention to the ratio of vowels to consonants. Obviously, if you wind up in the end game with 9 consonants and 0 vowels (or the reverse) you are in big trouble. Try to keep the vowel/consonant mix approximately even. If the board is vowel-heavy, start making small words with more vowels than consonants until the ratio evens out. If your board is vowel-poor, do the opposite and make a few words like "depth" or "tasks" to even things up. If you get through the middle game with a good balance of vowels and consonants, the end game will be a snap.
End game: When you get to the end game, the object should be to avoid using your blank or extra letters if at all possible. It may be better to make a few low scoring words and clear the board than make a high scoring word that requires you to use a blank tile on your next move. Plan ahead. Once the board is down to around 7 tiles, I don't make another word until I have a plan that accounts for all the remaining tiles.