It’s a fine line between simple enjoyment and out and out addiction, particularly with games – World of Warcraft being a perfect example. There are even iPhone apps around that are extensions of the game so that players can spend even more of their time living in the Warcraft Universe. Over time, more game apps have come out for iPhone which are extensions of full games originally programmed for console or desktop play.

Even when they’re not a part of a bigger game, iPhone games are becoming big business in their own right. As such makers are doing whatever they can to produce popular and addictive games. These can either be little timewasters or just miniature versions of other popular games. One thing that’s starting to emerge is that the top games are often very similar genres – such as tower defence games. A great example of a recent iPhone app that’s an extension of a game is the Kingmaker app which is part of the Fable 3 universe. It’s got players hooked before they’ve even bought or played the full game.

1 – Plants vs Zombies

Plants vs Zombies is created by Popcap games, well-known for time sucks like Bejeweled and Peggle. Voted one of the most popular games of the year, the port to iPhone just cemented its place as one of the most addictive and fun tower defence games on the app store.

2 – Angry Birds

Angry Birds was created by Rovio. Rovio are also responsible for Gem Drop & Mole War, two very good imitations of other popular games which are popular in their own right. Angry Birds is a fantastic fun version of the classic artillery game. Here you aim angry birds at the homes of the pigs who wronged them. A very classic game type but with a new take is so popular that expansions into other media are being proposed.

3 – Doodle Jump

Doodle Jump is created by Lima Sky which is already known for creating other iPhone games such as Crazy Frog and Crazy Egg. This is a simple ‘platform jumper’ concept that it is clear most of the attraction is due to the short span of the game. It’s a fun, and sometimes frustrating, way to kill a few moments while you wait in a queue, or sit on the train.

All 3 of these are great examples of how traditional and fairly simple game concepts can be turned into stylish and addictive games that claim thousands of new converts on mobile phones regularly.