Sonar Ruler vs CRuler

Sonar Ruler is a winner in the Best App Ever Awards - "Most innovative use of iPhone hardware" category! The Amazing New Sonar Ruler is an experimental app that uses echoes to measure distances with your iPhone! It uses the same principles that dolphins use to find food! It sends a short pulse from the speaker and measures how long that pulse takes to bounce off of something and return to the phone. It then estimates how far away you are. Use two devices to find the distance between them, without any wifi connection! Use "quiet" mode - with ultrasonic frequencies most people can't hear! Impress your friends with what this unique app can accomplish using only an iphone! GIZMODO.com: "that's a damned neat trick for a phone to be able to do." Features: - Set Units to feet, inches, or meters - Custom saved settings for measuring in different environments If you're a teacher, this app is a great way to teach students the principles of sonar, and how sound propagates through air. Enjoy! Follow us on twitter @LaanLabs NOTE: This is an experimental app, although it can be quite accurate, any measurements taken should be verified before using them.

CRuler: A personalized, versatile ruler right inside your iPhone. Turn your phone sideways and place the screen edge against the object—the scale is right before your eyes. Screws, jewelry, paper, parts, wires, fabrics—measure anything on the spot without rummaging through drawers for a tape measure. [Why the scale is reliable] The markings aren't just "rough estimates"—they are calculated based on the physical dimensions of your specific iPhone screen. [Measurement] • Full-screen landscape ruler: 1mm fine markings, 5mm medium markings, 1cm numerical markings, bolded every 5cm. Read at a glance. • 100cm range: Drag left or right to browse longer distances with natural inertia; the screen follows your finger smoothly. • Two-point measurement: Drag two dots to the ends of an object. cm, in, and cun (Chinese inch) are displayed simultaneously—no need to toggle between units. • Touch lock: Lock the measurement with one tap—it won't shift even if your hands shake. • One-tap reset: Instantly return the scale to the starting point. • Clean mode: Tap the screen to hide the toolbar for a distraction-free measuring surface. [Appearance] • 6 diffused themes: Neutral Retro White, Dark Series, Macaron Pink, Morning Ocean, Deep Sea Twilight, and Clear Sky Blue. You can also customize colors and use Hex codes for precise color picking. • Custom backgrounds: Pick an image from your album. Pinch to zoom and drag to compose; 6 background slots with an option for daily random rotation. • Auto-contrast: Automatically applies light markings for dark photos and dark markings for light photos—always readable. • Three display modes: Day, Night, and Follow System. [Feel] • Haptics: Triggered by distance while dragging; the faster you slide, the wider the intervals (can be disabled). • Skeuomorphic sounds: Deep, Neutral, and Crisp (can be disabled). • Glass-morphism UI: Toolbar and pop-ups automatically adapt to your system version. [Privacy] • No registration, no login, no ads, no in-app purchases. • Runs completely offline with no network requests. • Collects zero data and contains no third-party SDKs. • Photos are selected via the system PhotosPicker; it only reads the selected image and stores it locally on your device. [About Accuracy] Screen dimensions are based on public device specifications, and individual factory screens may vary. The scale provides reference measurements suitable for quick, daily measurements. For precision work, please rely on professional tools. [Who is it for?] DIY and crafts, jewelry resizing, hardware parts, e-commerce packing, repair and teardown, design prototyping, and those "I just need to measure this real quick" moments. It automatically detects your device model on first launch. If not recognized, simply tap the "Model" button and enter your screen's long edge once. Calibrate once, and it's ready to use every time.