What's New in Letos 4.0.3

Updated

Letos 4.0.3 adds relationship highlighting to the ERD editor. When you select an entity in a diagram, Letos now highlights the entities and connections related to it with a subtle glow effect, so you can trace relationships in a complex schema without manually following every line. The release was posted on 12 August 2026.

The headline feature: relationship highlighting

The ERD (entity-relationship diagram) editor is where you lay out tables and their foreign-key links visually. In larger schemas, a single table can connect to a dozen others, and the connecting lines quickly become hard to follow.

In 4.0.3, selecting an entity changes that:

  • Related entities are highlighted — the tables connected to your selection stand out from the rest of the diagram.
  • Related connections are highlighted — the lines joining them get the same treatment.
  • The effect is a subtle glow, not a hard color swap, so the overall diagram stays readable while the relevant path is emphasized.

The practical result: instead of tracing lines by eye, you click a table and immediately see its neighborhood.

When this helps most

  • Auditing a schema you didn't design, where you need to know what a table touches before changing it.
  • Reviewing foreign-key coverage — selecting a parent table shows which children reference it.
  • Presenting or explaining a data model, where you want to walk through one relationship cluster at a time.

How to use it

  1. Open your database in Letos and open the ERD editor for the schema you want to inspect.
  2. Click an entity (table) in the diagram.
  3. Read the highlight: the glowing entities and connections are the ones related to your selection.
  4. Click elsewhere or select a different entity to move the focus.

No configuration is mentioned for this feature — it appears to be on by default once you're on 4.0.3.

Getting the release

Letos is distributed as a download from letos.org. It is portable: the site states there is no need to install or uninstall — you download, decompress, and run. It runs on Windows, Linux, and macOS.

If you already run Letos, check the download options on the site for the 4.0.3 build. For the complete list of changes in this release, the news post and the ChangeLog are the places to look; the announcement excerpt above covers only the ERD highlighting feature.

Context worth knowing

  • Letos is free and open source under the GPL license, with no paid edition and no telemetry, per the project site.
  • It was formerly known as SQLiteStudio, so documentation and discussions from that era may still use the old name.
  • Windows code signing for the project is provided via SignPath.io, with a certificate from the SignPath Foundation.

If your work involves reading or editing SQLite schemas rather than just querying them, the 4.0.3 ERD highlighting is the reason to update. If you only run queries and never open the diagram view, this release changes little for your day-to-day use.