While there isn’t a single official "Beyblade Design App" from Takara Tomy or Hasbro that lets you 3D model custom parts from scratch, a vibrant ecosystem of community tools and official apps exists to help you design, simulate, and manage your Beyblades. 1.
For personalizing the look of existing Beys, hobbyists use graphic design tools to create custom "Bit Chips" or "Gear Chips." I Scientifically Created PERFECT Beyblades
For creators looking to design functional Beyblades for 3D printing, professional-grade modeling software is the standard.