紹介を通じてもらうことができる無料の追加容量について紹介相手にデスクトップ環境は必要ですか

I am a long-time Dropbox user, but I have started to consider the need to upgrade to a larger capacity version. I joined this community to investigate this issue. Thank you. First of all, my first question is:

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How much free space can you get through a referral? | Dropbox Help https://help.dropbox.com/ja-jp/accounts-billing/space-storage/how-much-free-space

I have a question after browsing the above.

According to this, it seems that the person you refer must have a desktop environment. If the person you refer only has a smartphone, am I correct in understanding that you cannot get additional storage space?