RuneBoard

RuneBoard is an experimental dual-screen Android keyboard designed primarily for the AYN Thor.

The project is currently in Prototype 1. Prototype 0 closed all Thor hardware gates; the current phase focuses on product-level visual hierarchy, setup/settings UX and regression-safe polish on top of that validated architecture.

Prototype controls

• D-pad: move keyboard selection
• A: press selected key
• B: backspace
• X: space
• Y: Shift -> Caps Lock -> off
• L1 / R1: move text cursor left / right
• L2 / R2: previous / next word
• Start: enter / active editor action
• Select: minimize
• L3: next language
• R3: accept primary suggestion
• Touch: direct key input

The DS-style controls are validated on AYN Thor hardware. Twelve editing actions can be remapped; D-pad navigation remains fixed. Left-stick keyboard navigation is also validated on the Thor while the IME view is active: each deliberate stick gesture advances one key, while D-pad hold uses delayed autorepeat.

Current implementation

Prototype 1 starts from the validated Prototype 0 foundation:

• a real Android InputMethodService;
• a touch QWERTY keyboard with a compact command row, an always-visible number row directly above the letters and a thumb-oriented bottom action row;\n- Prototype 1 keyboard chrome with a dedicated header surface, quieter command controls, stronger typing-key hierarchy and a more explicit selected-key halo;
• a narrowly scoped accessibility service for physical controller buttons;
• a separate keyboard model, state engine and controller mapper;
• geometry-aware D-pad navigation across rows with different key widths;
• L1/R1 cursor movement and L2/R2 word navigation through the active InputConnection;
• hold-to-repeat for D-pad navigation, Backspace, cursor movement and word movement, with touch autorepeat on repeatable editing keys;
• controller-first EDIT mode with Select All, Cut, Copy, Paste, Undo, Redo, Home, End, cursor/word navigation and character/word selection extension;
• a dedicated on-screen ↵ key that always inserts a newline, while the remappable physical Enter action (Start by default) keeps Android's contextual Go/Search/Send/Next/Done/Previous behavior;
• field-aware capitalization: sentence starts for prose, word starts for names/addresses, explicit Android cap flags when present, and no automatic caps for email/URL/password/non-text editors;
• persistent typing profiles for English QWERTY, Spanish QWERTY, French AZERTY and Russian JCUKEN;
• quick language cycling from L3 or the keyboard header;
• ABC/SYM mode switching without closing the IME;
• direct comma/period keys plus language-specific accent and punctuation pages;
• lower-display geometry that fills Android's available IME bounds without double-applying the navigation-bar inset;
• automatic IME presentation when an external text field gains focus, including a Thor-specific delayed show pass for the secondary display;
• system spell-check suggestions with up to three header candidates;
• touch or remappable R3 acceptance of the primary suggestion;
• conservative autocorrect on Space for strong typo recommendations;
• Suggestions and Autocorrect toggles, both enabled by default;
• persistent physical-button remapping with automatic conflict swapping;
• context-aware auto-capitalization plus manual one-shot Shift and persistent Caps Lock;
• action keys show the currently mapped physical button;
• four keyboard opacity levels;
• persistent background opacity across IME recreation;
• theme profiles: Default, OLED Black, Transparent and persistent Custom;
• custom settings UI with live theme/background controls, palette presets and key geometry;
• compact/minimized mode;
• standard Android clipboard actions without maintaining a private clipboard history;
• a setup/settings activity with live Android integration status and a built-in keyboard test field;
• unit tests for state, controller mappings and minimized capture policy;
• GitHub Actions running unit tests, lint and APK assembly;
• a dedicated Android emulator for non-Thor regression testing.

There are no third-party runtime dependencies.

Architecture

The product code is split into independent layers:

• keyboard/: layout, key model, ABC/SYM/EDIT state and keyboard engine;
• controller/: controller actions and Android key-code mapping;
• theme/: visual profiles, persistent custom-theme data and supported background-opacity levels;
• language/: typing-language profiles and layout metadata;
• editor/: editor-action resolution and input-field policy;
• suggestion/: word extraction, Android spell-check adapter and correction policy;
• settings/: persistent user preferences;
• RuneKeyboardView: rendering, touch hit testing and motion-event adapter;
• RuneBoardImeService: Android IME and InputConnection adapter;
• RuneBoardControlService: physical-button filtering while RuneBoard is active.

See docs/ARCHITECTURE.md.

Build

Current development version: 0.20.0-prototype

Current minimum Android version: Android 13 / API 33.

GitHub Actions runs:

1. unit tests;
2. Android lint;
3. debug APK assembly.

The successful workflow exposes RuneBoard-prototype-debug as an artifact.

Hardware validation

Prototype 0 was tested on an AYN Thor running Android 13 / firmware .377.

Validated on the physical device:

• AYN pins RuneBoard to the lower display while the editor remains on the upper display;
• touch input on the lower display writes into the upper-display editor;
• D-pad and A/B/X/Y controller typing, including delayed D-pad autorepeat while held;
• one-step analog-stick navigation with Android's synthetic D-pad compatibility events deduplicated;
• L1/R1 text-cursor movement and L2/R2 word navigation;
• EN/ES/FR/RU layout switching, persisted across IME recreation;
• L3 quick-cycle language switching;
• R3 primary-suggestion acceptance and touch-selectable candidate chips;
• conservative Space autocorrection for recommended typos;
• live physical-button remapping, including conflict swapping and reset;
• Shift/Caps state cycling and compact-mode Start pass-through;
• compact minimize/restore with controller pass-through;
• tuned background-opacity switching at 100%, 67%, 33% and 0%;
• controller/touch EDIT panel with clipboard and document-navigation actions.

On the test Thor, Android reports lower-display app bounds of approximately 1240x1025 px in landscape. The 0.17.1 full keyboard now fills the IME-provided height instead of using the earlier approximately 1240x595 px cap. Compact mode remains approximately 1240x134 px.

The lower panel is 1080x1240 native and 1240x1080 in landscape.

See:

• docs/PROTOTYPE_0_TEST_PLAN.md
• docs/PROTOTYPE_0_RESULTS.md
• docs/PROTOTYPE_1_RESULTS.md
• docs/EMULATOR_TESTING.md
• docs/CONTROLLER_MAPPING.md
• docs/LANGUAGES.md
• docs/LOCALIZATION.md
• docs/SUGGESTIONS.md
• docs/SYMBOLS.md
• docs/CUSTOMIZATION.md
• docs/EDITING.md

Emulator limitation

A dedicated Android 15 emulator can simulate a second 1240x1080 display and RuneBoard activities can run on it.

Stock Android still places the IME on display 0 even when the focused editor is on display 2. The emulator therefore cannot reproduce AYN's special cross-display IME policy.

Thor-specific display placement remains a real-hardware test.

Prototype 1 scope

Prototype 1 is the product-polish phase: keyboard visual hierarchy, setup/settings UX, theme consistency and regression-safe daily-use testing. It intentionally does not reopen the validated IME/controller architecture unless a regression requires it.

Swipe typing, cloud prediction, accounts, telemetry, Japanese composition and broad general-Android support remain out of scope for this phase.

See docs/PROTOTYPE_1_PLAN.md for the current product baseline and acceptance rules.

RuneBoard remains Thor-first. General Android support can be evaluated later.

Status

Build, unit tests and lint: passing.

Core Thor architecture: validated.

Prototype 0 hardware gates: complete.

Physical controller remapping, Shift/Caps, transparency and compact capture policy: validated on the real Thor.

Prototype 1 product/visual polish: in progress.

Experimental - not ready for daily use.

Contributing

Bug reports, feature ideas and focused pull requests are welcome. See CONTRIBUTING.md before opening one.

For security or privacy-sensitive reports, follow SECURITY.md instead of posting details publicly.

Support development

These projects are free to use and developed in my spare time. If they've been useful to you, you can help support future development.

_{All projects remain free regardless of support.}