Comparison

Polar Scope Align vs StellarMate

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

Head to head
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.

About

StellarMate

Control your astrophotography equipment remotely. Capture images, stream video, and perform precise alignment. Automatically back up your photos to the cloud with rich metadata for easy searching.

Highlights
  • Remote equipment control
  • Image capture and video streaming
  • Polar alignment assistant
  • Cloud image backup
  • Metadata search and sorting
  • Software updates
Features
Read full description

Use StellarMate App to discover and connect to your StellarMate controller. Control StellarMate functions and access the Web Manager and Web based VNC Viewer. Join StellarMate to your home WiFi network. Use Ekos to capture images, stream video, guide, focus, and align. With Polar Alignment Assistant tool, get very accurate polar alignment using internal astrometry engine. Never lose your images again with EkosLive Pro. All captured images are automatically uploaded to the cloud with a rich set of metadata that enables powerful search and sorting. Use custom tags to uniquely tag important frames for later use. Check the health of your device, and use the software updater to keep it up to date.

Screenshots

Polar Scope Align4 screens
StellarMate4 screens

Verdict

The call

The clearest difference is review sentiment: Polar Scope Align at 91% against StellarMate's 35%. Polar Scope Align also leads on rating (4.7 vs 2.9) and ratings volume (173 vs 26). StellarMate'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. StellarMate asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Polar Scope Align holds the better App Store score, 4.7 against 2.9. That said, the two scores are not equally well evidenced: Polar Scope Align has 173 ratings behind it against 26, so its average is the more settled of the two. Written reviews point the same way: 91% of Polar Scope Align's written reviews are positive against 35% of StellarMate's.

UpkeepUpdate frequency

Polar Scope Align ships an update every 6 weeks, StellarMate every 8 days. The most recent releases landed on October 24, 2026 and October 26, 2026 respectively.

Scorecard8 real differences · 2 level
Polar Scope Align versus StellarMate: the parameters behind the verdict, then further details
ParameterPolar Scope AlignStellarMate
PriceFreeFree
Rating4.7 (173 ratings) — better2.9 (26 ratings)
Positive reviews91.4% of reviews — better34.5% of reviews
Number of ratings173 — better26
Update frequencyEvery 6 weeksEvery 8 days — better
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better16.0
Further details — not scored
Size24 MB115 MB
Age rating4+4+
DeveloperDimitrios KechagiasIkarus Astronomy Company For Scientific Instruments & Tools

Customer experience

Polar Scope Align

All ratings173 ratings
Positive92.5%
Neutral0.6%
Negative6.9%
Written reviews174 reviews
Positive91.4%
Neutral1.7%
Negative6.9%

StellarMate

All ratings24 ratings
Positive50.0%
Neutral4.2%
Negative45.8%
Written reviews55 reviews
Positive34.5%
Neutral9.1%
Negative56.4%

Bugs and 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

StellarMate

Not enough reviews yet to summarise bugs or requests.

In-app purchases

3 purchases

Polar Scope Align

One-time3
  • Tip 1x$0.99
  • Tip 4x$3.99
  • Tip 10x$9.99
None

StellarMate

No in-app purchases

Questions

Is Polar Scope Align free?
Polar Scope Align is free to download, with in-app purchases available.
Is StellarMate free?
StellarMate is free to download, with no in-app purchases.
Which has better reviews, Polar Scope Align or StellarMate?
Polar Scope Align is rated higher. Polar Scope Align averages 4.7 out of 5 from 173 ratings, while StellarMate averages 2.9 from 26 ratings.
Do Polar Scope Align or StellarMate have ads?
Polar Scope Align shows ads; StellarMate does not.
Which is updated more often, Polar Scope Align or StellarMate?
Polar Scope Align ships an update every 6 weeks, and StellarMate every 8 days. Most recently, Polar Scope Align was updated on October 24, 2026 and StellarMate on October 26, 2026.

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