People play mobile games for all kinds of reasons, but for many casual gamers on the go, killing time is near the top of the list. Periods of restless immobility between engagements don't always result in real productivity, but for those who have the option of gaming and can't stand to turn off their brain for more passive play, word games are a great option. Engaging the mind's pathways with literate puzzles, word games can wake up an otherwise sleep-addled mind on a morning commute or straighten out a frazzled psyche after a long day at work. Continue reading to scope five great word games for most any casual mobile gaming situation on the iPhone and iPod Touch.

5. Word Warp
For what the $.99 Word Warp lacks in intrinsic beauty (and it does have some less-than beautiful graphics), it makes up for in value. Players are challenged to mine as many word combinations from a jumble within a set time limit. Challenges range in difficulty, but there's a certain sense of completion given each session's display of completed words in relation to a recommended total of possible combinations. There are certainly more expansive and challenging word games, but Word Warp is a good way for newcomers to get their feet wet before plunging into more difficult fare - especially with a free lite version to try before committing to the expanded full version.

4. Crosswords
Crossword gaming may have a way to go on a relatively small gaming device such as the iPhone, but for enthusiasts who can stomach a few inherent alterations to their game of choice, Crosswords is the solution to playing without pen and paper. It's got a fairly hefty $9.99 price tag, but when compared to free options like the New York Times app and the less expensive USA Today app, Crosswords affords players with the simplest layout and most concise clues, prompting casual play across multiple skill levels. Players also have their choice of crosswords from multiple publications, meaning there's really no end to how much they can play in a given time period. For those on the fence, there's a free version with enough rudimentary features available to learn the ropes.

3. Bookworm
With gameplay somewhere between Scrabble and Boggle, Bookworm gives mobile gamers a diagonal plane from which to form multiple word combinations. Essentially, the more words a player finds and strings together, the higher score they achieve. It's straightforward approach to scoring makes it suitable for all ages, meaning there's no shame in family members competing for high scores as they muscle through word history challenges. There's a seemingly unending directory of words to find given Bookworm's plentiful grid, so setting personal challenges shouldn't be a problem for those trying to rank up their personal best high score and finally wipe the smile off the omnipresent Bookworm mascot atop the screen.

2. Scrabble
While Hasbro's Scrabble has many mobile imitators, the original stands heads above the competition with the smoothest and least-cluttered interface and easy-to-master gameplay. It also plays much faster than its tabletop forbearer, meaning a single player can pick it up on the fly. The translation isn't flawless. Many of the social and tactile sensations associated with playing Scrabble with a group of friends on a tabletop can't be replicated and the features designed to make the game playable solo remove some of the more challenging and competitive aspects. Still, as either a diversion that strengthens word connections or as a training regime for the original game, it's a great way to get one's Scrabble on.

1. Quordy
A straightforward Boggle-style game (that just so happens to work and play smoother than Boggle's official mobile adaptation), Quordy challenges players to capture as many words as they can on a jumbled grid of letters. The mobile version is actually superior to its board game predecessor in that it tallies points and word counts automatically, making it one of the simplest word games to master and a choice option for picking up and playing on the iPhone. It may cost $1 more than the official Boggle, but its cleaner approach to the game makes Quordy a fantastic value for the casual word gamer.