Pokemon AlteRed (v2.3) is the latest version in the Pokemon AlteRed ROM hack series, building upon the previous v2.2 release. Again, this demonstrates continued development from the creators, suggesting iterative enhancements and refinements to the game's mechanics, story, or other features.  It's a fan-made creation and not an official product.

Pokemon AlteRed (v2.3)

Pokemon - Liquid Crystal Version