TimeTree vs Rockd
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
TimeTree
Explore a vast public knowledge base of evolutionary timescales and divergence times among organisms. This app uses a hierarchical system to find and present molecular time estimates from scientific literature, allowing users to compare species and view summary statistics.
- Explore evolutionary timescales
- View organism divergence times
- Access scientific literature data
- Hierarchical tree-based system
- Compute summary statistics
- Compare species divergence
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TimeTree 4 is a public knowledge-base for information on the evolutionary timescale of life. This application allows easy exploration of the thousands of divergence times among organisms in the scientific literature. A tree-based (hierarchical) system is used to identify all published molecular time estimates bearing on the divergence of two chosen organisms, such as species, compute summary statistics, and present the results. Names of two taxa to be compared are entered in the search window and the results are presented on a set of self-explanatory tabs. TimeTree 4 contains data from 2,274 studies including 50,632 species. We will be adding more data in the future as it comes in from researchers. TimeTree 4 requires iOS 8.0 or newer. The TimeTree project is jointly directed by Blair Hedges (Center for Biodiversity, Temple University) and Sudhir Kumar (Institute for Genomics and Evolutionary Medicine, Temple University). This project has been supported, in part, by grants from the National Science Foundation, National Institutes of Health, NASA Astrobiology Institute, and Science Foundation of Arizona.
Rockd
Discover and document the geology around you. Access global geologic maps, 3D globes, and detailed summaries of your surroundings. Contribute your own observations and track your exploration of Earth's geologic history.
- Interactive global geologic maps
- 3D virtual globe exploration
- Field observation logging
- Offline map caching
- Paleogeographic map access
- Stratigraphic column viewing
- Geologic literature integration
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Explore, learn about, and document your geologic surroundings! Whether you are a professional geoscientist or curious about the rocks around you and the stories they tell, Rockd allows you to explore and learn about the geologic record, contribute your own observations, and log your journey through the geologic record. Features: - Instant access to geologic and geographic summaries of your current location via a Dashboard - Interactive global access to more than 290 geologic maps, with more being added weekly - Explore the landscape with a dynamic, 3D virtual globe - Save maps for use in the field with a built-in map caching system - See your past location and explore paleogeographic maps from C.R. Scotese and GPlates - View Macrostrat stratigraphic columns where available (beta) - Explore published literature containing mentions of mapped geologic units (when available) via xDD (formerly, GeoDeepDive) - Elevation data for most points on Earth from digital elevation models (DEMs) - Add your own field observations even offline; tag features from Macrostrat and the Paleobiology Database - Record strike/dip or trend/plunge for geologic features, using your phone's compass - Track your progress through the geologic record privately, or share it with others - See the public activity of other users and share your own and other public checkins using unique URLs Rockd is produced by the Macrostrat lab in the Department of Geoscience at the University of Wisconsin - Madison. Support provided by the National Science Foundation (NSF) and the Dept. of Geoscience. Experiencing issues? Send an email to contact@rockd.org and we will do our best to help you resolve it.
Screenshots
Verdict
The clearest difference is rating: Rockd at 4.4 against TimeTree's 4.0. Rockd also leads on update cadence (every 3 months vs every 8 months) and ratings volume (185 vs 10). TimeTree's advantage is iOS requirement (8.0 vs 16.6). On price, ads, in-app purchases and monetization model 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. Neither carries in-app purchases, so what you see is what you pay.
Rockd holds the better App Store score, 4.4 against 4.0. That said, the two scores are not equally well evidenced: Rockd has 185 ratings behind it against 10, so its average is the more settled of the two. Written reviews point the same way: 65% of TimeTree's written reviews are positive against 74% of Rockd's.
TimeTree ships an update every 8 months, Rockd every 3 months. The most recent releases landed on October 16, 2026 and October 13, 2026 respectively.
| Parameter | TimeTree | Rockd |
|---|---|---|
| Price | Free | Free |
| Rating | 4.0 (10 ratings) | 4.4 (185 ratings) — better |
| Positive reviews | 65.1% of reviews | 73.6% of reviews — better |
| Number of ratings | 10 | 185 — better |
| Update frequency | Every 8 months | Every 3 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 8.0 — better | 16.6 |
| Further details — not scored | ||
| Size | 66 MB | 259 MB |
| Age rating | 4+ | 4+ |
| Developer | Arizona and Penn State Universities | University of Wisconsin-Madison Shared Apps |
Customer experience
TimeTree
Rockd
Bugs and requests
TimeTree
Not enough reviews yet to summarise bugs or requests.
Rockd
Reported bugs
17 issues- Black map display in airplane mode and online
- Persistent error dialogs that cannot be dismissed
- GPS not tracking in real-time
- Offline check-ins not syncing properly
- Sign-up page jumps between fields and login page
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- Fossils button not working
- Map returns to user location after viewing check-ins
- App crashes and becomes unresponsive
- Data loss after app reinstall or logout
- Maps fail to load after recent updates
- Location search functionality broken
- Android version windows not visible
- Straight lines appear when zooming
- Formations stop at state lines
- Check-in screen stuck with no exit option
- App won't load after initial use
- Geological overlay won't upload to base map
Requested features
16 requests- Follow/friend mechanic to track other users' check-ins
- Rock identification tool from photo uploads
- Offline map download with customizable zoom levels
- Stereonet tool for structural geology
- Groundwater/aquifer information section
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- Map legend/key for geological features
- Spanish language support
- Ability to move dashboard to different locations
- Latitude/longitude search functionality
- Multiple photo attachments per location
- Strike and dip data visualization
- Fault line labeling on maps
- Better Android version compatibility
- Tutorial or short course for advanced features
- Black contact lines between formations toggle
- Personal photo upload focus with mineral variations
In-app purchases
TimeTree
No in-app purchases
Rockd
No in-app purchases








