Comparison

ioda vs Polar Scope Align

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

ioda

This scientific application allows users to read and visualize data from various file formats commonly used in astronomy and high-energy physics. It supports formats like FITS, ROOT, HDF5, JPG, and FOG, and can execute specific script files.

Highlights
  • Read FITS, ROOT, HDF5, JPG, and FOG files
  • Browse and visualize data
  • Execute .kumac files
  • Includes gopaw core
  • Supports various scientific data schemas
Features
Read full description

ioda should be read "IO-DA", for Input/Output and for Data Analysis. It is a scientific application that permits to read files at various formats as FITS used in astronomy, ROOT and AIDA used in high energy physics (HEP), HDF5 with the g4tools data schema semantic, JPG format to store images and FOG developed at CEA/Saclay (France) to describe the LHC/ATLAS geometry. ioda permits to browse these files and visualise some of their data. Since 1.14.x, ioda contains the gopaw (=Good Old PAW) core and can execute .kumac files.

About

Polar Scope Align

This app calculates the precise position of celestial poles in your telescope's polar scope reticle for accurate alignment. It supports a wide range of reticles and corrects for atmospheric refraction, offering precision even at lower latitudes. Features include night mode, moon phase, and astronomical databases.

Highlights
  • Polaris/Sigma Octantis position calculation
  • Atmospheric refraction correction
  • Reticle centering error correction
  • Supports numerous reticle types
  • Red-color night mode
  • Moon phase and astronomical databases
Features
Read full description

Polar Scope Align is a free, ad-supported polar alignment app for iPhone and iPad. It calculates the position of Polaris or σ Octantis in your polar scope reticle for your location, date and time, helping you get a quick and accurate polar alignment with an equatorial mount. POLAR SCOPE ALIGNMENT • Accurate Polaris and Sigma Octantis position for your date and location • Atmospheric refraction correction for better accuracy, especially at lower latitudes - readings may differ slightly from simpler apps that skip this correction, but will agree with precise sources (USNO, scientific software) • Automatic time and location • Manual location support • Reticle centering-error measurement and correction • Zero-position help for common Celestron / Sky-Watcher / Orion style reticles • Full red night-mode interface SUPPORTED RETICLES Polar Scope Align supports 35+ polar scope and finder reticle types, including: iOptron, Astro-Physics RAPAS & PASILL, Takahashi (EM-10/11/200/400/500, NJP, PM-1, P2-Z), Sky-Watcher / Orion (including EQ6/AZ-EQ and Star Adventurer), Celestron, Meade, EXOS2, Bresser, Vixen (Atlux/SX/SXD/SXP/AXD/GP/GP-DX, Polarie), Astrotrac, Losmandy, Kenko, Avalon, Konus, Telrad, Rigel QuikFinder, and several older polar finders (Tuthill, Explore Scientific, Meade 9x60, Vixen Polaris, Celestron 7x50, Carton Optical). OBSERVING TOOLS The free version also includes: • Moon phase • Messier, Caldwell and bright-star database • DSS image downloads for included database objects • Saved, editable and printable DSO lists • 8 astronomy calculators for observing and imaging • Sample Pro tools available from Settings, including aurora forecast • iOptron WiFi Connect - report mount status, set mount Time/Date/Location LOOKING FOR ALIGNMENT WITHOUT A POLAR SCOPE? Polar Scope Align Pro adds the advanced tools many users search for: • Daytime / No Polar Scope Alignment • Camera Azimuth Calibration using the Sun, Moon, planets or bright stars • Laser / Hop Align for night alignment when Polaris is blocked • Push To / manual GoTo for non-GoTo telescopes • Live sky maps for Daytime Alignment, Laser / Hop Align, Push To and Hop To • Full 22,000+ object DSO database • Xasteria astro weather, aurora, satellite passes and widgets • 30+ calculators • Bubble level, compass and iOptron WiFi mount control • Apple Watch companion app • No ads If you only need accurate polar-scope alignment, this free version is a capable tool. If you want alignment without a polar scope, observing planning, weather and field tools, Pro is the complete version.

Screenshots

ioda1 screens
Polar Scope Align4 screens

Verdict

The call

The clearest difference is review sentiment: Polar Scope Align at 91% against ioda's 33%. Polar Scope Align also leads on rating (4.7 vs 3.0) and ratings volume (171 vs 2). ioda's advantage is in-app purchases (none vs 3) and ads (none vs shown). On price 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Polar Scope Align sells 3 one-off in-app purchases. ioda asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Polar Scope Align holds the better App Store score, 4.7 against 3.0. That said, the two scores are not equally well evidenced: Polar Scope Align has 171 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 33% of ioda's written reviews are positive against 91% of Polar Scope Align's.

UpkeepUpdate frequency

ioda ships an update every 5 months, Polar Scope Align every 2 months. The most recent releases landed on September 27, 2026 and October 14, 2026 respectively.

Scorecard8 real differences · 2 level
ioda versus Polar Scope Align: the parameters behind the verdict, then further details
ParameteriodaPolar Scope Align
PriceFreeFree
Rating3.0 (2 ratings)4.7 (171 ratings) — better
Positive reviews33.3% of reviews91.3% of reviews — better
Number of ratings2171 — better
Update frequencyEvery 5 monthsEvery 2 months — better
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS8.0 — better13.0
Further details — not scored
Size64 MB23 MB
Age rating4+4+
DeveloperGuy BarrandDimitrios Kechagias

Customer experience

ioda

All ratings2 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews3 reviews
Positive33.3%
Neutral0.0%
Negative66.7%

Polar Scope Align

All ratings171 ratings
Positive92.4%
Neutral0.6%
Negative7.0%
Written reviews173 reviews
Positive91.3%
Neutral1.7%
Negative6.9%

Bugs and requests

ioda

Not enough reviews yet to summarise bugs or requests.

Polar Scope Align

Reported bugs

6 issues
  • Date and time dial do not match correctly
  • GMT and LST times appear to be switched
  • App crashes or fails to initialize for some users
  • Alignment accuracy varies inconsistently between sessions
  • Location detection issues with cell tower vs GPS
Show 1 more
  • Reticle display not rendering properly in some cases

Requested features

7 requests
  • Online video tutorials demonstrating all features
  • Remove or reduce center dot size in reticle
  • Larger, bolder font options for better readability
  • Brighter star options for southern hemisphere alignment
  • Smaller ad button or ad customization
Show 2 more
  • Better beginner onboarding and instructions
  • More robust alternative alignment methods for southern hemisphere

In-app purchases

None

ioda

No in-app purchases

3 purchases

Polar Scope Align

One-time3
  • Tip 1x$0.99
  • Tip 4x$3.99
  • Tip 10x$9.99

Questions

Is ioda free?
ioda is free to download, with no in-app purchases.
Is Polar Scope Align free?
Polar Scope Align is free to download, with in-app purchases available.
Which has better reviews, ioda or Polar Scope Align?
Polar Scope Align is rated higher. ioda averages 3.0 out of 5 from 2 ratings, while Polar Scope Align averages 4.7 from 171 ratings.
Do ioda or Polar Scope Align have ads?
Polar Scope Align shows ads; ioda does not.
Which is updated more often, ioda or Polar Scope Align?
ioda ships an update every 5 months, and Polar Scope Align every 2 months. Most recently, ioda was updated on September 27, 2026 and Polar Scope Align on October 14, 2026.

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