Compass · Bubble Level

A precise digital compass and bubble level in one app, wrapped in a classic brass instrument theme.

A brass compass over a parchment nautical chart; a brass level over a drafting blueprint — the look and feel of vintage navigation tools.

Powered entirely by your device sensors — no internet connection is required for the core features.

■ Features

• Digital compass — azimuth + 8-point cardinal direction (N/NE/E/SE/S/SW/W/NW). Brass dial with red/navy needle illustration.

• Bubble level — real-time pitch (front/back) and roll (left/right) visualization. Bubble color reflects state (green / yellow / red).

• Sensor calibration — fine-tune offsets yourself (Settings → Calibration).

· Compass: slider for azimuth offset (±30°), or one-tap "Set current as 0°".

· Level: place the device on a flat surface and tap "Apply as level" to capture the current reading as an offset.

· Calibration is saved persistently.

• Classic vintage theme — fixed brass + cream palette, consistent regardless of the system dark mode.

• Nautical chart (CARTA MARINA) and drafting blueprint background illustrations reinforce the instrument feel.

• Settings screen redesigned as rounded bubble cards.

• Auto-rotation aware — UI and sensor coordinates stay consistent in portrait and landscape.

• Foldable/tablet aware — the dial and frame resize automatically to fit the available vertical space.

• Calibration prompt — alerts you when magnetic sensor accuracy drops and recommends a figure-8 motion.

• Smooth animations — 50Hz sensor input interpolated to your 60fps display.

■ Privacy

Compass does not collect any personal data on its own.

The only data sent off-device is what Google/AdMob requires to serve and measure ads. In the EEA the GDPR consent prompt is shown, and you can change consent any time under Settings → Ad Privacy Options.

■ Ads

• App-open ad: at most once every 15 minutes when bringing the app to the foreground (frequency managed by AdMob).

• Adaptive banner: a single banner pinned to the bottom of the screen.

• Prefer no ads? Use Settings → In-App Purchase → Remove Ads. One-time purchase, restorable on other devices via "Restore Purchases".

■ Permissions

• Internet: for ads, in-app review, in-app billing, and the open-source license screen.

• Advertising ID: used only for ad measurement (not used after the Remove Ads purchase).

Questions or feedback: sia@siamakerlab.com