Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.
Arduino IDE vs XOD opinions
Not really an alternative ; XOD is more Visual than Arduino IDE.
KTechLab is an IDE for microcontrollers and electronics. It supports circuit simulation, program development for microcontrollers and simulating the programmed microcontroller together with its application circuit.