Frequently asked questions

An email client for iPhone that replaces the traditional inbox list with a flow of AI-prioritized cards. It summarizes, orders, and drafts the first version of your replies — you triage with a swipe and reach inbox zero in minutes.

At launch, Gmail accounts — one or several — brought together in a single unified inbox. Other providers (Outlook, iCloud) are on the roadmap for later phases.

An iPhone running iOS 16 or later. For now Lumen Mail is iOS-only; there's no Android version at launch.

Never. The AI generates drafts and reply suggestions, but nothing leaves your account without you reviewing and confirming the send. You always have the final say.

The AI combines signals — senders you exchange with most, direct questions and deadlines, your reply history, and the importance you've already marked. Nothing is permanent: the more you use it, the better it gets.

Yes. The AI uses samples from your sent emails to capture your style. You dictate, it transcribes and builds an editable draft — you adjust whatever you like before sending.

Partly. Already-synced mail is cached on your iPhone, so you can read and triage your inbox without a connection. Semantic search and asking questions about your inbox run on our servers, so those need you to be online.

No. Your mail is never used to develop, improve, or train any AI model — ours or our providers'. The AI companies we use (Anthropic and Voyage AI) process your messages under terms that forbid training on them, and personalization stays inside your own account. See the full policy on the Privacy page.

To prioritize and search your mail, we keep a synchronized copy of it — plus the search index and your Gmail tokens, encrypted — on our servers. Your iPhone holds a cache of that mail for offline reading, along with your triage decisions and preferences. Disconnect the account and the server copy is deleted; the Privacy page explains exactly what's stored and how to erase it.

Reading your inbox and manual triage are free. The AI features — voice replies, semantic search, and advanced prioritization — are part of Lumen Mail Pro.

Billed annually, with a free trial before your first charge. You can cancel anytime through the App Store.

Through the App Store itself, in Settings › your account › Subscriptions. Cancellation stays in effect until the end of the period you've already paid for.