Triatlas vs Eclipse Simulator
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Triatlas
Explore the cosmos with a comprehensive star chart featuring millions of celestial objects, including stars, galaxies, and nebulae. Customize your viewing experience with night vision, orientation controls, and intuitive navigation.
- Detailed star catalog (up to mag 12.6)
- Extensive galaxy and nebula data
- Support for clusters and double stars
- Flexible night vision mode
- Adjustable orientation controls (flip/mirror)
- Chart-to-chart navigation
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The Triatlas app contains the most detailed, speedy star chart available for smartphones and tablets! - Stars up to mag 12.6 - Galaxies up to mag 15.5 (PGC). 37000 in total! - 1200 planetary nebulae - 1800 open clusters, all globulars - Others: SH-2, RCW,LDN / Barnard - Double stars whose main star is brighter than 11th magnitude (35,000 double stars) - Variable stars whose maximum reaches the 12.5 magnitude (29,000 variable stars) PLUS: - Flexible Night vision mode - Landscape-portrait mode - Flip and mirror (Supporting telescope orientation) - Chart-to-chart navigation using the black corners. Based on the charts made by Jose Torres. Used with permission.
Eclipse Simulator
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Eclipse Simulator is an educational and investigative tool for finding unusual solar and lunar eclipses by combining an observing location, horizon conditions, and long-term Earth-rotation variation (ΔT). Its search catalog spans astronomical year -999 (1000 BCE) through 5000 CE. Study each event through maps, a ground-level view, and contact times. Key features • Search solar and lunar eclipses by date range, eclipse type, location, and other available criteria. • Narrow the search with an observing location, solar horizon conditions near sunrise or sunset, lunar moonrise or moonset, and ΔT. • View solar-eclipse center and limit lines, partial-eclipse regions, and lunar-eclipse visibility on Apple Maps. • Choose an observing location and play the changing alignment of the Sun, Moon, and shadow from the ground. • Inspect the contact times that exist for the event, including C1–C4 for solar eclipses and P1–P4/U1–U4 for lunar eclipses. • Compare the standard ΔT model with alternative scenarios to understand how uncertainty affects historical and future timing and paths. • View stars and constellation lines adjusted to the selected event time instead of showing today’s sky. • Share the selected event as CSV or JSON and the displayed screen as PNG or PDF. On iPhone, the app uses focused screen-by-screen navigation. On iPad, its wider layout keeps the catalog and event workspace within easier reach. If you grant location access, it is used only to set the observing point to your current location. You can also select a point on the map or enter coordinates. About time and accuracy Results are modeled values derived from the ephemeris, ΔT model, and Earth-orientation model recorded with the bundled data. The broad search catalog includes a low-precision analytical ephemeris, while the calculation provenance for a selected event is shown in the app and exports. Uncertainty remains in ΔT, future civil-time rules, polar motion, lunar-limb terrain, local terrain, and weather. Historical and future views use present-day Apple Maps and do not reconstruct borders or cities from the selected era. Lunar-eclipse color is schematic. Use the app for education, understanding astronomical geometry, and comparing model assumptions. Do not rely on it as a guaranteed value for observation planning, navigation, scientific conclusions, or safety-critical decisions.
Screenshots
Verdict
The clearest difference is update cadence: Eclipse Simulator at every 4 days against Triatlas's every 13 months. Triatlas's advantage is iOS requirement (6.1 vs 18.0). 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
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Triatlas ships an update every 13 months, Eclipse Simulator every 4 days. The most recent releases landed on September 25, 2026 and October 6, 2026 respectively.
| Parameter | Triatlas | Eclipse Simulator |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (15 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 15 — better | — |
| Update frequency | Every 13 months | Every 4 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Mac |
| Requires iOS | 6.1 — better | 18.0 |
| Further details — not scored | ||
| Size | 465 MB | 3.2 GB |
| Age rating | 4+ | 4+ |
| Developer | DDQ | Fumikazu Kondo |
In-app purchases
Triatlas
No in-app purchases
Eclipse Simulator
No in-app purchases





