From 2004 to 2007 DHGames were working on a GBA racing game similar to Excitebike, but sadly their publisher changed its mind later and the project was never released to the market, even if it was finished. The game was later reworked and it’s now coming out for the Nintendo DS (maybe? It seems that the official DHGames site is down, maybe they have closed down and the DS version is cancelled too). A rom of the original GBA version was shared online by the same developers, so it can be played and preserved by the community instead of being lost forever. Props to DHGames!
In April 2010 Motocross Challenge was finally released for the iPhone / iPod Touch, so at least it was not lost at all! You can see some videos of the iPhone version in DHGames’ YT Channel or buy Motocross Challenge from the iTunes Store (only $0.99!)
Thanks to Celine for the contribution!