Comparison

Adopt vs REDACt EU

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Adopt

Access real-time data from autonomous oceanographic floats that record seismic activity. View instrument locations, trajectories, and health parameters. This app provides a low-cost method for oceanic data collection.

Highlights
  • View MERMAID instrument locations
  • Access recent trajectories
  • Obtain ocean depth information
  • View instrumental metadata
  • Identify instruments by name and institution
Features
Read full description

Adopt-A-Float allows users to access trajectory metadata and state-of-health parameters of the EarthScope-Oceans MERMAID fleet. MERMAID, short for Mobile Earthquake Recording in Marine Areas by Independent Divers, is a long-lived drifting autonomous float equipped with a hydrophone capable of recording acoustic waveforms generated by distant earthquakes. Most earthquakes occur at or near plate boundaries, yet most seismic monitoring stations are on dry land. Deployed but not recovered, telemetering data in near-real-time, MERMAIDs are uniquely positioned as a low-cost alternative for geophysical and environmental oceanic data collection. Diving down to a typical parking depth of 1500 m below the ocean surface, they passively drift with the ocean currents, recording the ambient acoustic wavefield, identifying earthquake signals, and surfacing to report those, on average every 4-7 days with the current settings, which are expected to give them a five-year life span. When at the surface, MERMAID collects GPS location and time information and communicates with the IRIDIUM satellite constellation using RUDICS. Using this iOS app you can: View the current location of all MERMAID instruments View their most recent trajectories and obtain information about ocean depth View instrumental metadata such as battery level and instrument pressure readings Identify the instruments by name and by operating institution Developed by Tenzing Sherpa ©2021 by Frederik J Simons (www.frederik.net) Let us know what you think! Give us feedback via https://github.com/tenzingsherpaa/AdoptAFloat-3.0/issues We acknowledge support from the U.S. National Science Foundation (www.nsf.org) under grants OCE-1917058 and EAR-1150145 (CAREER), and from Princeton University. MERMAID was designed by scientists and engineers and is now built by OSEAN SAS (www.osean.fr), from which it is commercially available. EarthScope-Oceans (www.earthscopeoceans.org) is an organization founded by a multidisciplinary group of geoscientists who are coordinating efforts to create a global network of sensors that monitor the Earth from within the oceanic environment. As other organizations are doing for the land-based seismological communities today, EarthScope-Oceans shepherds national projects into the international arena where globally relevant, applicable, and mutually agreed-upon decisions can be made on instrument development, science objectives, data management, and outreach.

About

REDACt EU

Read full description

REDACt is a powerful earthquake monitoring app which delivers all of the information you need, with push notifications included, all free of charge. It also includes a beautifully simple design optimized for the latest versions of iOS.

Screenshots

Adopt3 screens
REDACt EU4 screens

Verdict

The call

The clearest difference is update cadence: REDACt EU at every 3 weeks against Adopt's every 40 months. REDACt EU also leads on iOS requirement (13.0 vs 17.5). On price, ads, in-app purchases 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Adopt ships an update every 40 months, REDACt EU every 3 weeks. The most recent releases landed on September 26, 2026 and October 8, 2026 respectively.

Scorecard2 real differences · 8 level
Adopt versus REDACt EU: the parameters behind the verdict, then further details
ParameterAdoptREDACt EU
PriceFreeFree
Rating5.0 (1 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings1 — better—
Update frequencyEvery 40 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.513.0 — better
Further details — not scored
Size1 MB84 MB
Age rating4+4+
DeveloperFrederik SimonsRedvector SRL

In-app purchases

None

Adopt

No in-app purchases

None

REDACt EU

No in-app purchases

Questions

Is Adopt free?
Adopt is free to download, with no in-app purchases.
Is REDACt EU free?
REDACt EU is free to download, with no in-app purchases.
Do Adopt or REDACt EU have ads?
Neither Adopt nor REDACt EU shows ads.
Which is updated more often, Adopt or REDACt EU?
Adopt ships an update every 40 months, and REDACt EU every 3 weeks. Most recently, Adopt was updated on September 26, 2026 and REDACt EU on October 8, 2026.

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