Pokemon Online is described as 'Pokémon Online is the most up to date pokémon battle simulator around the block. It was made in C++ and Qt frameworks. Download the latest version of Pokémon Online simulator and experience competitive battles in real time with trainers from all over the globe'. There are six alternatives to Pokemon Online for a variety of platforms, including Mac, Windows, Linux, Online / Web-based and Android. The best alternative is Taming.io, which is free. Other great apps like Pokemon Online are Pokemon Showdown (Free, Open Source), Tuxemon (Free, Open Source), OpMon (Free, Open Source) and Shoddy Battle (Free, Open Source).
Pokemon Laboratory is the latest version of the original 4th generation Pokemon simulator, Shoddy Battle. This project is a near 100% rewrite of the original program that strives to be a 100% accurate recreation of Pokemon battle mechanics.