Please, visit for a multi-platform and updated version of this app, for which an offline mode will soon be available.

Observe the sky like a pro.

iObserve pushes your preparation of astronomical observations to a much higher level. It gathers all the information you need when observing the sky with small and big telescopes, and let you manipulate your nights and targets. It has been built from the ground up by a former ESO support astronomer in Chile.

-- What others have said:

• Best in its class (5 stars) "There is no other app for planing astronomical observations like iObserve. Because of its all-in-one approach, iObserve is also a discovery machine, allowing the user to make connections that were not obvious. And this is perhaps the best thing that can be said about any app. And the author has an amazing roadmap for the app, I can only hope he achieves it. Truly stellar, well done!" (a happy austrian user)

• "Must have for serious astronomers" (5 stars) "Every observer with a mac should have this app, and observers without a mac should buy a mac so they can use this app. It has proven invaluable on multiple observing runs both in the planning phase an while observing." (a happy US user).

• "Efficient observing " (5 stars) "I witnessed the development of this app from its early beta versions and am pleased that it turned out to be much more stable and clean. I use it everytime I go observing at large observatories [...]." (a canadian "Some Dude")

• "iObserve" (5 stars) "The Application works extremely well. I needed support and it was very efficient, i had an answer in a few hours." (some enthusiastic italian 'Mr. Fox')

• "A must have app for all serious astronomers" (5 stars) "This little application has now matured very nicely from its origins a few years ago. (...) It will appeal to serious astrophotographers, deep sky enthusiasts and – of course – professionnal astronomers. Yes, you can find the same information if you scout around the web, but iObserve puts it all in once place, and a lot more besides. I couldn't work without it. And the developer, Cédric, provides outstanding support." (a nice follower from Australia).

iObserve allows you to:

• Easily import any known in SIMBAD or not-yet known object, browse the Exoplanets catalogue or download the latest JPL ephemeris of any known comet and asteroid. All object parameters, properties and references will automatically be kept up-to-date.

• Draw and track multiple colored airmass curves for about 100 builtin observatories on Earth, and get the objects sorted according to the best observing time,

• Draw multiple star tracks with builtin or custom horizon masks, and follow targets across the sky, within customisable night boundaries,

• Find automatically the closest standard stars among 21 000 optical and near-infrared (spectro)photometric or telluric stars stored in 6 different catalogues,

• Download the SDSS, DSS, 2MASS and AAVSO finding charts in multiple photometric bands and with numerous options,

• See the Moon's airmass curve, along with its age, coordinates and illumination fraction, and its minimum separation to any object,

• Easily convert fluxes and magnitudes between different units, et get immediate extrapolations in every bands of the Johnson, Cousins, Strömgren, TYCHO2, SDSS and 2MASS systems,

• Easily convert object coordinates between equatorial, celestal (sidereal) and galactic systems, for any epoch in various units,

• Convert times and dates, and see how the Earth shadow is placed on the world map, relative to your position and that of your observatories,

• Convert small and large distances, and, like all other conversions, save it for future reference.

Moreover, iObserve lets you create new observatories – being a remote location, a professional observatory or simply your backyard. You will then be able to use it like any other builtin observatory.

iObserve also provides its famous times bar with Local Time, UT, Julian Date and the Sidereal Time for all its observatories.

What’s New

Version 1.7.6

Adding a little preference (in the "Airmass" preference tab) to choose the origin of the azimuth (South or North).

Ratings and Reviews

4.2 out of 5
11 Ratings

11 Ratings

astrojill ,

Great for astronomers

I love this app, very useful during an observing run!

c2gptucdncnsgp ,

Used to love it but now keeps crashing

This is great app for planning observations professionally and easily. Unfortunately lately every time I select an object from the left bar the app completely crashes and I always have to add the object anew to be ablet to vsualize it without making everything crash. Since I observe the same targets many times that’s a bit annoying. Any idea how to fix? Thanks

wglow ,

Amazing tool for exoplanet observations

Wow, this is an amazing app for exoplanet observations. The tab for transit information tells you specificially when the next transit will occur— this makes planning for an imaging sesson so easy!! The only addition that would be nice would be to have is a column in the exoplanet data listing the magnitude for each object.

App Privacy

The developer, CEDRIC FOLLMI, has not provided details about its privacy practices and handling of data to Apple. For more information, see the developer’s privacy policy.

No Details Provided

The developer will be required to provide privacy details when they submit their next app update.


  • Family Sharing

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