Postr Postr is a small Android Nostr composer. Write a note, sign it with Amber, and publish it to your relays. Private keys stay in Amber. Search for people to mention by name, including names with several words. Matching accounts you follow appear first. Profiles and completed searches are cached locally and reused for repeated searches. Load a preview for a bare web domain without changing the text of your post. Pasted Nostr note and article references have opt-in cards with verified event content. Quote inserts a nostr: reference. Published references carry NIP-18 quote tags. Verified reference events are cached locally. Nostr cards have a separate, labelled browser action that opens njump.me. Keep separate local drafts for multiple accounts, attach files through Blossom, or start dictation with an installed Android speech provider. Speech processing depends on the selected provider. The durable outbox survives unreliable connections. Postr reads back and verifies the exact signed event before reporting success, and retries reuse the same event. The app has no feed, advertising, or analytics.