Smart Ruler: Tape & Caliper

Turn your smartphone into a clear, high-precision vernier caliper, dual-axis bubble level, 2D area calculator, and screen ruler tape! Smart Ruler eliminates the calibration flaws of traditional ruler apps by offering 1-touch physical calibration against standard reference cards or coins for dependable real-world precision.

Designed with a refined, modern dark studio aesthetic and tactile micro-haptics, Smart Ruler delivers the fluid feel of mechanical measuring tools combined with digital sub-millimeter precision.

KEY FEATURES & CAPABILITIES

📏 DUAL-CALIPER VERNIER PRECISION MODE
• Measure small objects by placing them directly on your screen.
• Dual independent calipers (Cyan & Amber) with 48dp ergonomic touch handles.
• Sub-millimeter & fractional micro-nudge steppers (±0.1 mm / ±0.01 inch).
• 1-Touch Screen Freeze Lock: Freeze calipers to record measurements without thumb slippage.
• Zero-Reset button for instant relative differential measuring.

💳 1-TOUCH PHYSICAL CALIBRATION WIZARD
• Standard credit cards (ISO/IEC 7810 ID-1: exactly 85.60 mm) allow instant 1-touch screen calibration.
• Coin presets included: US Quarter (24.26 mm), 1 Euro (23.25 mm), 1 Rupee (21.93 mm), 100 Yen (22.60 mm).
• Continuous fine-tuning scale slider (0.700x – 1.300x) with hardware display metrics baseline.

🟢 DUAL-AXIS BUBBLE LEVEL & INCLINOMETER
• Digital bullseye spirit level for surface leveling and shelf alignment.
• Real-time roll and pitch angle readouts powered by internal motion sensors.
• Visual level lock indicator and haptic confirmation when surface is balanced.

🔲 2D AREA GRID & SURFACE CALCULATOR
• Interactive 2D rectangular grid calipers.
• Measures length, width, and surface area simultaneously.
• Dynamic readouts in mm², cm², or square inches (in²).

🔄 VERSATILE MULTI-UNIT CONVERTER
• Millimeters (mm) & Centimeters (cm)
• Decimal Inches (in)
• Precision Architectural Fractions (1/16" and 1/32" with simplified denominators)
• Zero-jitter tabular figure numerals (tnum) for smooth real-time tracking.

🎨 3 CURATED THEMES
• Dark Studio: Deep obsidian slate base with glowing cyan and amber accents.
• Pitch Black AMOLED: True #000000 background for power saving and sharp contrast.
• Crisp Minimalist Light: Clean, high-contrast surface with etched measurement ticks.

🌐 GLOBAL MULTI-LANGUAGE LOCALIZATION (16 LANGUAGES)
Fully localized with 100% key parity across English, Spanish, German, French, Japanese, Arabic (with full RTL mirrored layout), Hindi, Portuguese, Simplified Chinese, Traditional Chinese, Russian, Korean, Italian, Indonesian, Turkish, and Vietnamese.

🔒 PRIVACY & INTEGRITY
• 100% on-device measurement processing.
• Zero personal tracking or unnecessary permissions.
• Keeps screen awake while measuring so your work is never interrupted.

Engineered with passion by Shuttle Technologies.
Support: [email protected]
Developer Apps: https://play.google.com/store/apps/developer?id=shuttletechnologies