i3Plus+ adds new features to your printer. Ever wanted to preheat your printer to a specific temperature instead of the original firmwares PLA and ABS presets? With i3Plus+ you can create your own presets!
Wanhao's original firmware is based on an old outdated version of Marlin. i3Plus+ is more up-to-date with newer Marlin releases, so you aren't missing out on bugfixes and new features!
Although Wanhao has released the source code for an old version of their firmware, they aren't communicating changes and keep the source code of newer versions behind locked doors. i3Plus+'s source code is publicly available, so everyone can tweak and customize it to their needs.