Gravity 360 is a two-dimensional colour-matching puzzle game by Lemonquest.
Grorbs is a simple puzzle game where you have to make all the on-screen orbs green instead of red. Changing the colour of one orb changes the colours of others nearby, which complicates matters somewhat.
Hang man is the classic pen-and-paper puzzle game where you have to guess a word or phrase one letter at a time. The game contains thousands of words and phrases divided up into categories.
Hexxagon Labs is a modern reworking of the classic Othello/Reversi concept, with a board made up of hexagons, games involving two or three players, and the occasional hole in some boards.
A number-based puzzle game, but it's not Sudoku! The aim of Hidato is to fill in a grid with consecutive numbers, with lines going horizontally, vertically or diagonally.
Hidden Expedition: Titanic challenges you to scour the wreck of the RMS Titanic for lost artefacts before your oxygen runs out.
Hobbies WordSearch is a word search game with grids automatically generated from a database of over 25 categories (e.g. art, board games, knitting etc). The skill level and grid size can be adjusted from the main options menu, so if you find the game too easy you can make it a lot harder. It automatically keeps track of your time at each skill level and informs you how well you've done after each game.
IQ Booster is an example of the brain training genre and gives you various mental challenges in maths, logic and general knowledge. There are also various game modes including a pass-around (aka hotseat) multiplayer mode.
Jenga is based on the popular real-life game where you remove wooden blocks from a tower without making it collapse.
Kenken is a number-based puzzle game similar to sudoku but with slightly different rules.
A simple-but-cheap game: try to swap the black and white playing pieces in as few moves as possible. The game keeps track of your best scores, so you can try to beat them.
Labyrinth Lite is a simple game where you have to physically tilt the phone to guide a ball through a maze. The different kinds of ball have different physical properties, and the holes in the maze must be avoided in order to reach the goal. This is a cut-down free version of the commercial game Labyrinth Touch, which has a lot more levels.
Labyrinth Touch is an accelerometer-based game where you physically tilt the phone to guide a ball through mazes. This is a much larger version of the freeware game Labyrinth Lite, with the same gameplay but a lot more mazes to complete.
Lexulous is the new name for the game Scrabulous which was a big hit on Facebook. It's essentially the same game as Scrabble but using a different name. The name "Scrabulous" caused legal difficulties for the publishers as it was so close to "Scrabble", so they changed it to "Lexulous".