No, you don't have to declare that in India. Anyway it's very less amount, it is okay.
Also, in Japan, VAT refund is not introduced yet, so it's instant tax exemption of presenting your passport at the store (min purchase value, 5000 JPY).
However, for Apple products, official Apple stores have stopped giving tax-free (there was a whole scandal with 🇨🇳 people abusing the system). Other big chains like Bic Camera or Yodabashi Camera give that, you can purchase from there.