Lagrange 1.5.4

First of all, good news for everyone: the BookOrbit maintainer has confirmed that they are hard at work on an official BookOrbit Android client. You can follow the update in this issue comment. I really cannot wait to see it.

What does this mean for Lagrange? Lagrange will continue to be maintained and will not be abandoned. At the same time, support for other book servers is now part of the roadmap, including Audiobookshelf, Komga, Kavita, CWA, and others. The goal is to support those servers and bring the Lagrange reading and listening experience to them as well.

Do we have a timeline? Not really. The plan and preparation work are already underway, so stay tuned.

Features

• c615bb4 Added EPUB 3 read-along narration for supported local publications. (PR #185, #182)
  • Highlight the currently narrated sentence and advance through the publication.
  • Start playback from a selected sentence and save narration resume state locally.
  • Provide audiobook-style speed, skip, and close controls.
• ae351e0 Added explicit BookOrbit OIDC SSO sign-in through the server-hosted WebView flow. (PR #177, #4)
  • Support provider discovery, PKCE, state and nonce validation, callback handling, and pending-destination recovery.
• acfbd48 Reorganized application settings into clearer Appearance, General, Library, Downloads & Offline, and Network & Sync categories. (PR #179, #178)
• 01973bf Added a global option to hide Android's navigation bar while reading EPUB, PDF, and comic content. (PR #183, #181)
  • Keep EPUB progress and reader menus above the visible navigation-bar inset when the option is disabled.
• 3def972 Added live whole-number book and chapter percentages to the expanded audiobook player. (PR #176, #169)
• df6ba6d Added an adjustable audiobook speed overlay with immediate persistence and fixed two-decimal labels. (PR #175, #168)

Improvements

• f2869ae Kept reused audiobook Media3 sessions aligned with the current audio-focus preference. (PR #174, #153)

Fixes

• 4a77a20 Fixed read-along lifecycle handling across backgrounding, screen lock, notification actions, paused-state skips, and volume-button behavior. (PR #186, #182)
  • Continue narration through app backgrounding and screen lock.
  • Apply audiobook-style audio-focus handling.
  • Provide one custom notification with the current sentence and transport controls.
  • Keep Android hardware volume buttons assigned to system volume while read-along is active.
  • Keep chapter changes in the EPUB reader menu rather than the read-along player.

Others

• Lagrange 1.5.4 continues to support BookOrbit's dedicated audiobook API introduced in BookOrbit v2.10.0.
• The default release download uses the combined APK name Lagrange-1.5.4.apk.
• Architecture-specific alternatives use Lagrange-1.5.4-x86.apk, Lagrange-1.5.4-x86_64.apk, and Lagrange-1.5.4-arm.apk when published.
• If you are unsure which architecture to choose, download the plain combined APK.
• Native AppAuth/Custom Tabs remains deferred until BookOrbit provides deployed mobile-redirect support.
• MOBI, AZW, AZW3, and FB2 remain unsupported.

Validation

• 752 JVM unit tests passed, with zero failures, errors, or skips.
• lintDebug passed.
• Debug and Android-test APK assembly passed locally.
• The release workflow performs signed release assembly using the repository's GitHub Actions secrets and publishes the combined and architecture-specific APK assets.
• Android-test sources compiled but were not executed because no connected device or emulator was available during release preparation.

Upgrade notes

• No migration action is currently identified for the 1.5.4 changes.

Future Android distribution plans

Android is tightening restrictions around sideloaded applications, so we are considering releasing Lagrange on the Google Play Store.

Will Lagrange be a paid app? Yes and no:

• The GitHub APK will always remain free of charge.
• The Play Store version is planned as a one-time, low-cost purchase for the convenience provided by the Play Store environment, including automatic updates and app verification.
• Both versions will be exactly the same. No features or functions will be locked behind the Play Store version.

We will not start this process soon. The current plan is to consider Play Store distribution only after Lagrange supports some servers other than BookOrbit. Advanced users who are comfortable sideloading an unverified APK will be able to continue using the free GitHub version, while the Play Store option will be available for users who prefer its installation and update experience.