Anchor Pro vs Buoyancy Calc
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Anchor Pro
This app helps boaters set and monitor their anchor position in real-time. It allows for defining safe zones, tracking boat movement, and receiving alerts for critical changes. Remote notifications and Apple Watch integration enhance its utility for secure anchoring.
- Set anchor location in real-time or manually
- Define custom safe swing zones
- Monitor boat movement and track history
- Receive real-time alerts for position, GPS, and battery
- Remote notifications via Telegram or email
- Apple Watch companion app for key metrics
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SET THE ANCHOR Set your anchor location in real time as you drop it, or specify it later by entering distance and bearing. Advanced users can also input exact coordinates. DEFINE THE SAFE ZONE Define the allowed swing area as a simple circle around the anchor, or create a more precise zone by setting two different radii at specific angles. MONITOR MOVEMENT Stay on top of every movement with comprehensive real-time data. Review key metrics on the main screen or switch to the map view to see your boat's track — ideal for analyzing whether your anchor is holding or dragging. GET ALERTED WHEN IT MATTERS Monitor position, GPS signal strength, and battery level — and receive alerts the moment any of these fall outside your set thresholds. REMOTE ALERTS Leave your phone on board and stay informed from shore. Receive alarm notifications via Telegram or email. With Telegram, you can also request a live status update at any time. APPLE WATCH Keep distance, bearing, and battery level on your wrist with the Apple Watch companion app — all updated in real time. TRY ANCHOR PRO FOR FREE Core features are always free. Want to explore everything? All premium features are available during a free trial period — no commitment required. Anchor Pro is ad-supported. Purchasing an Anchor Premium subscription removes ads and unlocks extra features. Payment is charged to your iTunes Account at confirmation. Subscriptions renew automatically at the same price unless auto-renewal is turned off at least 24 hours before the current period ends. You can manage auto-renewal anytime in your Account Settings. Anchor Premium is $6.99 USD/year (pricing may vary by country). Any unused portion of a free trial is forfeited upon purchasing a subscription, where applicable. Terms of use: https://links.ideaboys.net/anchor-ios-terms.html GOOD TO KNOW Anchor Pro uses background audio and location services to keep alerts active when the app is not in the foreground. Please note that continuous GPS use will drain your battery faster than usual.
Buoyancy Calc
Calculate the optimal weight for scuba diving based on environmental factors. Input your weight, water type, tank, and exposure suit to get a suggested weight for neutral buoyancy.
- Calculate suggested diving weight
- Adjust for water type
- Adjust for tank type
- Adjust for exposure suit
- Supports pounds and kilograms
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Quickly find out the suggested weight you should add when scuba diving in different environments. Based on PADI's Peak Performance Buoyancy basic weighting guideline*. Enter your weight in pounds or kilograms, and additionally set the type of water, tank, and exposure suit to dial in a suggested amount of weight to help keep you neutrally buoyant. *Note that this app and the developer are not officially a representative of PADI. This app will give the user a good estimate of the weight needed for the environment selected, but there are always adjustments needed to achieve peak performance, based on gender, physique, exposure suit age, accessories, etc.
Screenshots
Verdict
The clearest difference is rating: Anchor Pro at 4.8 against Buoyancy Calc's 3.1. Anchor Pro also leads on review sentiment (79% vs 40%) and ratings volume (3.6K vs 25). Buoyancy Calc's advantage is in-app purchases (none vs 1) and iOS requirement (15.6 vs 17.2). On price, update cadence, ads and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Anchor Pro sells 1 in-app purchase, starting at $6.99 per year. Buoyancy Calc asks for nothing beyond the download.
Anchor Pro holds the better App Store score, 4.8 against 3.1. That said, the two scores are not equally well evidenced: Anchor Pro has 3.6K ratings behind it against 25, so its average is the more settled of the two. Written reviews point the same way: 79% of Anchor Pro's written reviews are positive against 40% of Buoyancy Calc's.
Anchor Pro ships an update every 2 months, Buoyancy Calc every 3 months. The most recent releases landed on October 23, 2026 and October 22, 2026 respectively.
| Parameter | Anchor Pro | Buoyancy Calc |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (3.6K ratings) — better | 3.1 (25 ratings) |
| Positive reviews | 78.9% of reviews — better | 40.0% of reviews |
| Number of ratings | 3.6K — better | 25 |
| Update frequency | Every 2 months — better | Every 3 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | Free — better |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod |
| Requires iOS | 17.2 | 15.6 — better |
| Further details — not scored | ||
| Size | 23 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | IdeaBoys GmbH | Eric Hamiter |
Customer experience
Anchor Pro
Buoyancy Calc
Bugs and requests
Anchor Pro
Reported bugs
2 issues- App randomly shuts off
- Anchor position tracking glitches
Requested features
3 requests- Customizable anchor icon/color
- Integration with marine GPS/chartplotter
- Ability to adjust alarm parameters remotely
Buoyancy Calc
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Anchor Pro
- Anchor Premium7 Days trial$6.991 Year
Buoyancy Calc
No in-app purchases









