Drive Mould King building-block RC toys over Bluetooth
About this app
Control Mould King building-block RC toys from your phone over Bluetooth: no Raspberry Pi, no network, fully open source.
MoldQueen is a standalone Android app for driving Mould King building-block RC toys. It uses the phone's own Bluetooth radio and serves its control interface on the device, so it needs no Raspberry Pi, no network, and no cloud account. It speaks a reverse-engineered Bluetooth Low Energy broadcast protocol, and follows a "thin transport, smart client" design: the radio just broadcasts the toy's control telegrams, while the on-device client resolves every control to a channel and owns the per-toy mapping.
Control layouts Each toy gets a control surface, and any toy can fall back to a generic one: • A model-specific Excavator (Mould King 13112) dashboard with left and right tracks, arm, front arm, rotation, and bucket. • Generic, model-agnostic layouts (a 12-axis controller and a brick-style gamepad) that drive any Mould King MK4 model on these hubs. • Proportional drag joysticks and press-and-hold buttons. • Per-channel speed caps, channel inversion, and a RAW channel view for direct control.
Auto-assign Map a new toy's motors to channels in a few taps: • Pick a motor profile (tracked vehicle, car with steering, or custom) and a motor count. • The app assigns each motor to a slot and channel; adjust any row by hand.
Gamepad Drive with a physical controller instead of touch: • Pair a Bluetooth controller (for example a DualSense) and steer with the sticks. • Touch and gamepad work interchangeably.
Safety Stopping is built in: • An emergency STOP control that cuts all motion at once. • Auto-neutral keepalive: every active channel must be refreshed continuously, so a channel that stops being refreshed returns to neutral on its own. A dropped connection or a released control coasts back to a stop instead of running away.
Languages • Six interface languages: English, German, Chinese, Korean, Spanish, and French.
Open and independent • Free software under the MIT License; the full source is on GitHub. • The Mould King MK4 protocol was reverse-engineered for interoperability with hardware the author owns, for educational and personal use. • Builds on J0EK3R's MIT-licensed MouldKingCrypt work, ported byte-for-byte and verified against the stock app's adverts. • A private, independent, unofficial hobby project. Not affiliated with, authorized by, endorsed by, or sponsored by Mould King; "Mould King" is used only descriptively for interoperability.
Licensed under MIT, by Dr. Jens Richter.
What's New in v0.1.2
Imported from the F-Droid repository index.
Version history
Jul 2, 2026 · 26.9 MB · Android API 31–35 · code 10200
Imported from the F-Droid repository index.
SHA-256 823e65481fa68be1f4ff6793796842cfcc43b49f50aa06b0b304ae7d79769e61
Will it run on your device?
60%
- Targets newer Android builds, so legacy devices may be excluded.
- ABI coverage is focused on newer 64-bit devices.
- Aligned with the latest Android target SDK expectations.
Installation Guide
Open Settings on your Android device
Go to Security → Unknown sources (or Install unknown apps)
Enable "Allow from this source" for your browser or file manager
Open the downloaded APK file from your Downloads folder
Tap "Install" and wait for installation to complete
Launch the app from your home screen
Make sure to re-enable Unknown Sources restrictions after installation for security.
How to install this safely
How to verify the file you downloaded
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What the signing certificate proves
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How to roll back to an earlier version
No earlier build is on record for MoldQueen, so there is nothing to roll back to yet. When a second version is published, this section will explain how to move between them safely.
Why we list sources instead of hosting everything
The official store channel is almost always the right choice: it updates automatically and carries the publisher's own distribution guarantees. A direct APK is useful when a device has no store access, when a rollout has not reached your region, or when you need a specific version — and only when the publisher has authorized that copy. APKBrowse does not list pirated, cracked, or unauthorized rebuilds of MoldQueen, and a listing is removed when the evidence for it stops holding up.
Get MoldQueen
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Other sources
F-Droid listing
officialF-Droid builds this app from source and signs it. This is its official listing, with older builds and full release notes.
Source code
verified publisherThe upstream repository this build is compiled from.
We check legality and signature continuity, but device behaviour still varies. Install at your own discretion.
App Information
Security Verification
We record provenance; we do not run malware scans. Verify the hash yourself before installing.
SHA-256 Hash
823e65481fa68be1f4ff6793796842cfcc43b49f50aa06b0b304ae7d79769e61
Signing certificate
f40a1372de890d73b5eb252e4a2d584b884713e330aba76936f52101dc34ff93
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Previous Versions
No earlier build is on record — this is the first release we have listed.
The signing certificate fingerprint for this release is on record, so a build that does not match it did not come from this publisher.
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