I hope the other grandparents do not feel compelled to compete ... to try to buy a toy that he’ll like better. He’s better off if we work together.
I buy a few toys, but I primarily buy him books (and clothes when I can afford it). It is really easy to give a toddler his / her own smartphone or tablet, but harder to read with the child, tell stories (complete with motions and sound effects), walk and run in the yard, roll / toss / bounce a ball back and forth, and point at clouds ☁️ and stars ✨ in the morning / evening sky. But I’m of the opinion that the latter is a lot better for the child than the former.
(I am not anti-technology. I just think small children especially need a lot more grounding in the physical world they live in, and a lot more running around. I’m amazed at how much heavier today’s toddlers are than they were thirty to forty years ago.)