How to throw away broken smartphones?

I have a broken smartphones from my country. How do I throw it? Are there any collection point in Tokyo? FYI: I can not speak Japanese.

Yes, there are collection points. Which "ku" or "shi" in Tokyo do you wish to throw it away in?

I live in Itabashi, work in Minato. But anywhere in tokyo is okay. Do i need to pay? How about the procedure?

You can also bring it to a big electronics store like Bic or Yodobashi. Some have English-speaking staff.

I do not buy the phone from that shop, so I think I can't throw it there.

You can throw away your smartphone and various other small electric devices at electric appliance stores, even if you don't do/haven't done any shopping there. It will not cost you. The rare metal in the devices will be utilized.

Other than the stores, here is a list of collection sites in Itabashi-ku. Click the phrases in blue and you can automatically jump to a map. The top one at 2-66-1, Itabashi is your Itabashi City Hall, and they have a box in the basement.
http://www.city.itabashi.tokyo.jp/c_kurashi/055/055706.html

This is a similar list for Minato-ku. Note that this is automatic translation.
https://minato.j-server.com/LUCMINATO/ns/tl.cgi/https%3a//www.city.min...

If you have trouble finding the collection box, just go to a clerk, point at your smartphone and say that it is "trash" or "waste" and they would understand.

thank you so much for the answer!!! it really help me a lot