Keryx Mail Wants to Put Your Whole Personal Server in One Android App

Field notes

Keryx organizes mail, calendars, contacts, and tasks around a direct connection to a configured server, with JMAP as its primary protocol and several established DAV and mail protocols for compatibility. The page specifically says server address books remain the source of truth, while an optional bridge can expose them to Android Contacts. It also describes blocked remote images, Keystore-backed credential encryption, and the absence of advertising or analytics SDKs. The product is identified as an Android pre-release.