The budget of this film was 30 million dollars. An average Pixar film costs about 200 million.
Entirely produced using Blender 2.79b (animation) and Cycles (Blender's native render engine). Blender is a free and open software developed in the Netherlands and financed by companies and people from all over the world.
The brief scenes showing Mai's father show him with the likeness of John Krasinski, who voiced 7723. This links her absentee real father with 7723 who quickly becomes a father figure to Mai.