Here's "Mini Suduko", which was requested by Louise. It's a quicker, possibly easier version of the popular number puzzle Sudoku. Instead of the usual 9x9 grid, Mini Sudoku uses a 6x6 one.

How To Play:
Each diagonal, row, column and 3x2 block must contain one, and only one of the digits 1,2,3,4,5 and 6 in any order.
Controls
There are two input modes:
- Red - number input
- Blue - direction input
- 0 or Call - changes input mode
Directional mode
- 2 - move up
- 8 - move down
- 4 - move left
- 6 - move right
- You can also move with the arrow keys.
Number mode
- Press any number between 1 and 6

Type: Ad-Supported
Vendor: GoMobili
Data Connection Required: yes
Supported iDEN phones: All Falcon Series (MIDP-2 - i856, i776, i465, i9, i290, etc.)
File Size: 78 KB KB

As requested here's a crossword puzzle app. MoxWord is easy to use, fits all screen sizes and the keys are mapped correctly. The only downside is that there are only three puzzles - but that's two more than the only other working free crossword app I've been able to find. The MoXWord web page says "When you've finished playing all the crosswords, you simply get the next set." but there doesn't seem to be any way to actually do that in the app or online.

Type: Freeware
Vendor: Sutherland Studios - Product Page
Data Connection Required: No
Supported iDEN phones: All Falcon Series (MIDP-2 - i856, i776, i465, i9, i290, etc.)
File Size: 48 KB

A fiendishly difficult maze puzzle.  The maze is wrapped around itself inside a 3D pipe. When you get completely frustrated turn on cheat mode ("show right way") in the options and follow the green dots (shown in the image) to the exit. Adapts to all screen sizes. There's an online map generator on the author's site for creating your own mazes (not tested). Slow but playable on the i776 and similar phones, it should be fine on the i9, i856 and i680.

Type: Freeware
Vendor: mjsoft - Product Page
Data Connection Required: No
Supported iDEN phones: All Falcon Series (i856, i776, i465, i9, i290, etc.)
File Size: 83 KB

A strategy puzzle game that's a little like Reversi but with simpler rules.

The object of the game is to flip all of the black pieces to white in as few moves as possible. Clicking a piece flips it's color and the color of any pieces next to it horizontally or vertically.  It's much harder than it sounds!

Best on 128 px wide screens (i290, i465, etc.) doesn't fill larger screens.

Keys: Arrow move cursor, Call flips pieces.

Type: Freeware
Vendor: Innograte AB - Product Page
Data Connection Required: No
Supported iDEN phones: All (MIDP-1) with Java  (i290, i335, i465, i776 i856, i9, etc.)
File Size: 12 KB

I know some of you are looking for Collapse style games. Dwindle is a clone of the original Collapse.

To play, delete groups of three or more blocks of the same color by highlighting one of the blocks and pressing the Call key. New rows of  blocks constantly get added to the bottom of the screen. If you let the blocks reach the top of the screen you lose.

Points are awarded for each block deleted with bonus points for deleting larger groups of blocks. The goal is to score as many points as possible without letting the blocks reach the top of the screen.

Keys: Arrows, 2, 6, 8, 4 - Move Cursor
Call: Delete blocks

Type: Freeware
Vendor: Innograte AB - Product Page
Data Connection Required: No
Supported iDEN phones: All (MIDP-1) with Java  (i290, i335, i465, i776 i856, i9, etc.)
File Size: 25 KB

Cotopia's online version of the Connect 4 parlor game.  Players take turns dropping coloered balls into a grid.  The first payer to get four balls in a row horizontally, vertically or diagonally wins. You can play against a robot or another person online.

Keys: The OK key doesn't work, use the Call key instead to drop balls.

Type: Freeware
Vendor: Cotopia - Product Page
Data Connection Required: Yes
Supported iDEN phones: All with Falcon Series (MIDP 2) with Java and 128px wide screens  (i290, i335, i425, i455 i465, i776, etc.) Also available for other screen sizes here.
File Size: 57 KB

Keys: The OK key doesn't work, use the Call key instead to drop balls.

Type: Freeware
Vendor: Cotopia - Product Page
Data Connection Required: Yes
Supported iDEN phones: All with 176x220 px screens ( i855, i856, 1885, etc.) Available for other screen sizes here.
File Size: 61 KB

Keys: The OK key doesn't work, use the Call key instead to drop balls.

Type: Freeware
Vendor: Cotopia - Product Page
Data Connection Required: Yes
Supported iDEN phones: Motorola i9 Also available for other screen sizes here.
File Size: 64 KB

This version of  Sudoku features an unlimited number of puzzles, game saving,  two difficulty levels, a game creator, a cheat mode and changable backgrounds.  The game adapts to all screen sizes.

Keys: For ease of use press the left softkey (labeled Menu) and set "Input Mode" to "Numpad + Joypad"
In this mode use the arrow keys to move the cursor and the number keys to enter numbers.

Type: Open Source
Author: PhonPhun - Product Page
Data Connection Required: No
Supported iDEN phones: All  (MIDP-1) with Java  (i290, i335, i465, i776 i856, i9, etc.)
File Size: 59 KB

Find the five words hidden in the puzzle before time runs out.

To play: move the cursor to the beginning or end of a hidden word and press 5 to select. Then move the cursor to the end of the word and press 5 again.

This game is designed for 128 x 176 px screens (i465, i776). It doesn't fill larger screens and the bottom row letters is hidden on smaller ones..

Keys:
2 = Up, 8 = Down
4 = Left, 6 = Right
5 = Select, OK
0 = Show hint

Type: Ad-Supported
Vendor: Artificial Life, Inc.
Data Connection Required: Yes
Supported iDEN phones: All Falcon Series with Java. Best on 128 or 176 px wide screens (i465, i776, etc)
File Size: 79 KB