To search by meaning, MindDuck prepares a search index for every text. A small model built into the app does it: texts and queries don't go anywhere, and the index is stored encrypted.
The index is built after new messages and documents, after a history import and on a new device. After an import, chats can be found by title right away, and search by meaning is completed in the background, starting with newer conversations.
Background tasks
The Background tasks button shows what is happening right now:
| State | What it means |
|---|---|
| Preparing local search | The index is being built |
| Waiting for shared search data | The device is waiting for ready data from another device |
| Local search paused | You paused the build |
| Local search is waiting | The build is postponed and will continue by itself |
| Local search needs attention | Some data couldn't be processed; click Retry |
| Local search is ready | Everything is ready |
You can use the app while the index is being built. Pause and Resume pause and continue it.
Phones and large archives
Building the index loads the processor and the battery. A large archive is easier to import on a computer: the phone then receives ready data through sync. If the phone has to build it, keep MindDuck open and plug the phone into a charger.
Updated October 7, 2026 · for version 0.2.12 · Found a mistake? Write to us