# Exoplanet Explorer vs Hubble Space Telescope Tracker

The clearest difference is review sentiment: Exoplanet Explorer at 100% against Hubble Space Telescope Tracker's 0%. Exoplanet Explorer also leads on rating (4.6 vs 1.0) and ads (none vs shown). Hubble Space Telescope Tracker's advantage is iOS requirement (12.0 vs 18.0). On price, in-app purchases and monetization model there is nothing between them.

Both are free to download. Exoplanet Explorer sells 4 in-app purchases, starting at $2.99 per 3 months and Hubble Space Telescope Tracker sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Exoplanet Explorer holds the better App Store score, 4.6 against 1.0. That said, the two scores are not equally well evidenced: Exoplanet Explorer has 70 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 100% of Exoplanet Explorer's written reviews are positive against 0% of Hubble Space Telescope Tracker's.

Exoplanet Explorer ships an update every 2 weeks, Hubble Space Telescope Tracker every 3 months. The most recent releases landed on October 25, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | Exoplanet Explorer | Hubble Space Telescope Tracker |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (70 ratings)](https://appshunter.io/ios/app/exoplanet-explorer/id1457614833/reviews)** | [1.0 (2 ratings)](https://appshunter.io/ios/app/hubble-space-telescope-tracker/id6468819172/reviews) |
| Number of ratings | **70** | 2 |
| Positive reviews | **100.0% of reviews** | 0.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Every 2 weeks** | Every 3 months |
| Monetization | Freemium | Free with in-app purchases |
| Size | 171 MB | 72 MB |
| Requires iOS | 18.0 | **12.0** |
| Devices | **iPhone, iPad, Mac, Apple Watch, Vision Pro** | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Carsten Knoblich](https://appshunter.io/developer/541438854) | [KAKHA GIORGASHVILI](https://appshunter.io/developer/1501353984) |

## What reviewers say

### Exoplanet Explorer

[App page](https://appshunter.io/ios/app/exoplanet-explorer/id1457614833)

Explore a vast catalog of over 6,000 confirmed exoplanets with detailed scientific data. Compare worlds, visualize habitable zones, and track new discoveries. Ideal for stargazers, students, educators, and researchers.

**Highlights:** 6,000+ confirmed exoplanets, Detailed scientific data, Advanced filtering and sorting, Planet comparison tool, Habitable zone analysis, Home screen widgets, Apple Watch companion app

**Features:** Family Sharing, Apple Watch app

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 3 months subscription | $2.99 | per 3 months |
| 12 months subscription | $6.99 | per year |
| Big supporting tip | $2.99 | one-time |
| Really big supporting tip | $4.99 | one-time |


### Hubble Space Telescope Tracker

[App page](https://appshunter.io/ios/app/hubble-space-telescope-tracker/id6468819172)

Follow NASA's Hubble Space Telescope mission in real time. Explore a gallery of stunning images, engage in discussions, and learn about space. Receive notifications for new discoveries and test your knowledge with quizzes.

**Highlights:** Real-time mission progress, Image gallery, Discussion forums, Notifications for new images, 3D Solar system model, Ask an Astronomer feature

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium | $2.99 | one-time |


## Frequently asked questions

### Is Exoplanet Explorer free?

Exoplanet Explorer is free to download, with in-app purchases available.

### Is Hubble Space Telescope Tracker free?

Hubble Space Telescope Tracker is free to download, with in-app purchases available.

### Which has better reviews, Exoplanet Explorer or Hubble Space Telescope Tracker?

Exoplanet Explorer is rated higher. Exoplanet Explorer averages 4.6 out of 5 from 70 ratings, while Hubble Space Telescope Tracker averages 1.0 from 2 ratings.

### Do Exoplanet Explorer or Hubble Space Telescope Tracker have ads?

Hubble Space Telescope Tracker shows ads; Exoplanet Explorer does not.

### Which is updated more often, Exoplanet Explorer or Hubble Space Telescope Tracker?

Exoplanet Explorer ships an update every 2 weeks, and Hubble Space Telescope Tracker every 3 months. Most recently, Exoplanet Explorer was updated on October 25, 2026 and Hubble Space Telescope Tracker on October 12, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*