Game Boy Advance (6-11-01) 

Game Boy Advance, like the original Game Boy has gone through a few different models over time. For the most part, they are all the same with minor changes here and there. Below is a list of them all. 

Colors: Indigo, Glacier, Arctic, and Fuschia. Limited Edition Platinum and various others.
Screen: No backlight. After the Platinum GBA, a more vibrant screen was used, but still lacked a backlight.
Plays: Game Boy, Game Boy Color, Game Boy Advance

Game Boy Advance SP (03/23/03) 

All the Game Boy goodness you could ever need. This version of the GBA comes with a front-lit display for night time play. Since it features the same TFT screen that the first GBA had, you can also play in the sunlight. Quite possibly the best feature of this iteration is that it can play all your past Game Boy games. There are only a few such as Kirby’s Tilt ‘n’ Tumble that don’t work with it. 

Colors: Platinum, Black, Red, Blue, Tattoo, Target, Toys R’ Us, others…
Screen: A front-lit screen. Seemed kind of washed out, but looked great in the sun.
Plays: Game Boy, Game Boy Color, Game Boy Advance

Game Boy Micro (09/19/05) 

The trendy Game Boy. This version plays only Game Boy Advance games and is much, much smaller than any of the previous models. A key feature is the system’s replaceable faceplates that allow you to change the system’s look to fit your personality…or something like that. More faceplates should be available in the near future.

Colors: Black, Silver
Screen: Very bright and small screen. Hard to see in the light, but awesome in the dark.
Plays: Game Boy Advance

New Game Boy Advance SP (Unknown) 

Essentially, this unit is identical to the other SP model. The only difference is that it has a back light like that of the DS or Game Boy Micro. Other than that, it comes in two new colors.

Colors: Charcoal and Baby Blue.
Screen: The secret update was a back-lit screen similar to the DS’s screen.
Plays: Game Boy, Game Boy Color, Game Boy Advance.