To understand how galaxies have formed, astronomers need your help to classify them according to their shapes. If you're quick, you may even be the first person to see the galaxies you're asked to classify. Images come from telescopes including Hubble and the Sloan Digital Sky Survey.

This app caches several subjects locally so you can classify even while offline and have the classifications automatically uploaded later.

To learn more about the Galaxy Zoo project and our science, visit

*** The sequence of questions is determined by the Galaxy Zoo project and is consistent with the web UI.

What's New

Version 1.19

Uses the latest Galaxy Zoo survey (Gama 15).

Ratings and Reviews

App doesn't work that well, but the content is beautiful

First time runner.

Update: the app isn’t working at all anymore. It hasn’t worked since the last major iOS update. :(

I LOVE looking at galaxies. I could do it all day, every day. When I look at them, I imagine all of the life that's out there living in them somewhere at this very moment. It's literally thousands of worlds of possibilities in each little galaxy that comes up. Fascinating!

That said ,the app itself needs a lot of work. It crashes and sometimes refuses to load any content until I delete and reinstall it. Other times, it randomly loads options for some galaxies and not others. It's far from ideal. I'll put up with it in order to spend hours staring at the wonders of the universe, and to help, but a better app would be pretty awesome, just sayin'. ;)

Does not work


This app does not work.

The Universe in Your Pocket

Galiliam Galilei

A great app! I've always found Galaxy Zoo classifying to be surprisingly fun, and this app makes classification portable, an easy way to put free time to use, and MUCH faster/more efficient than using the site on my laptop (which I wasn't expecting)! It loads each step in the blink of an eye and it's easy to breeze through dozens of galaxies in a few minutes, provided you've gone through the training course online.

Improvements I'd love to see:

-A way to save favorite galaxies, like on the site

-The ability to zoom in on images (they're quite small on the iPhone) and invert the colors

-The ability to skip galaxies... I occasionally find a certain galaxy a little too challenging for the moment and would rather move on to a new image

Overall though, a great start to the Galaxy Zoo app. A must for all astronomy geeks and hobbyists. This app won't be for everyone though, and will be a waste of time without going through the classification training on the Galaxy Zoo site first.


Murray Cumming
11.2 MB
Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch.
English, German
Age Rating
Rated 4+
© Murray Cumming


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    With Family Sharing set up, up to six family members can use this app.

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