Upstream
ActiveAI-nativeThe first inbox designed for humans and agents
What it does
Your inbox, handled for you. Upstream's agents sort the noise, draft replies in your exact voice, follow up at the right time, and do what you ask - like finding receipts or scheduling meetings - so you can fly through your inbox and have fun doing it.
Its site says now · captured 2026-08-23
Upstream
Upstream is a messaging app for teams, built on top of email.
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