It is Gmailify serving the "unlimited", not Google. No ToS violation - not using Google's APIs. Gmailify is an extension of existing features of Gmail.
Many Gmail users already do this, but through a complete service like Fastmail, Migadu etc. Gmailify provides a thinner layer made for this purpose specifically.
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Somehow I feel like there's a ToS violation in here.
Not me being dismissive, just me reconciling the definition of "unlimited" with the very limited constraints of Google's APIs
It is Gmailify serving the "unlimited", not Google. No ToS violation - not using Google's APIs. Gmailify is an extension of existing features of Gmail.
Many Gmail users already do this, but through a complete service like Fastmail, Migadu etc. Gmailify provides a thinner layer made for this purpose specifically.