GWL vs WaveDepth
Price, ratings, monetisation and update history for both apps, side by side โ with what reviewers say about each.
GWL
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This app scans for Ground water sensor and reads the depth of water
WaveDepth
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WaveDepth estimates how deep the water is by watching what waves do as they cross it. In deep water a wave barely feels the bottom. As the seabed rises the wave slows, its crests bunch together, and it grows taller โ wave shoaling. How much taller depends only on the depth and the wave period, so measuring that change at several points along the wave's path recovers the depth at each one. All you need is one brightly coloured floating ball and a steady place to rest your phone. HOW A MEASUREMENT WORKS 1. Register your ball. Circle it once in a photo and enter its real diameter. That single number sets the scale for everything that follows. 2. Film the water. Up to two and a half minutes, split into five 25-second sections with a five-second gap between them. Move the ball to a new spot during each gap. 3. Mark the ball in each section. You get one frame per section โ circle the ball on each. That fixes its size and colour for tracking that stretch of water. 4. Read the depth. The app follows the ball twenty times a second, measures the wave period from both the ball's motion and the water around it, and reports a depth for every section. WHAT YOU SEE Every section gets its own card: the depth, the camera-to-ball range, the wave amplitude and how it compares with the reference section, the period used, the ball's width in pixels, the scale at the ball, and the phone's tilt. Open the diagnostics on any section for the frames analysed, the detection rate, the tracking confidence, the drift removed by the fit, and any period estimates that were measured but deliberately left out of the calculation. Nothing is hidden behind a summary. If a number looks wrong, the numbers behind it are there too. ALREADY HAVE MEASUREMENTS? Manual mode takes a wave period and a set of amplitudes and returns the depth profile directly, with no filming required. ON YOUR DEVICE All video analysis runs on your iPhone. Nothing is uploaded, no account is needed, and the app makes no network requests of its own. Available in English, Spanish, French, Portuguese, Japanese, Korean and Simplified Chinese. PLEASE READ These depth readings are rough estimates and can be inaccurate. Do not rely on them for navigation, safety, or any real-world decision. WaveDepth is a tool for curiosity and experiment โ it is not a depth sounder and not a charting instrument. The developer accepts no responsibility for any use of these results.
Screenshots
Verdict
The clearest difference is update cadence: WaveDepth at monthly against GWL's every 14 months. GWL's advantage is iOS requirement (13.0 vs 15.1). On price, ads, in-app purchases and device support there is nothing between them.
Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
GWL ships an update every 14 months, WaveDepth monthly. The most recent releases landed on October 3, 2026 and October 13, 2026 respectively.
| Parameter | GWL | WaveDepth |
|---|---|---|
| Price | Free | Free |
| Update frequency | Every 14 months | Monthly โ better |
| Ads | No | No |
| In-app purchases | No | No |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 13.0 โ better | 15.1 |
| Further details โ not scored | ||
| Size | 10 MB | 24 MB |
| Age rating | 17+ | 4+ |
| Developer | Smart Sensor Devices AB | Jin Hwa Lee |
In-app purchases
GWL
No in-app purchases
WaveDepth
No in-app purchases









