Comparison

AsterScope vs Sky Map

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

Head to head
About

AsterScope

Features
Read full description

AsterScope is the transparent stargazing planner built for real observers — from first-time binocular users to seasoned deep-sky hunters. Instead of dumping a wall of coordinates, it answers the question you actually care about: "Is tonight worth setting up?" EXPLAINABLE TONIGHT PLAN Every plan is scored on five independent pillars — Sky clarity, Moon friendliness, Dark hours, Gear fit, and Target quality — and visualized as a five-axis radar chart. You see at a glance which pillar is dragging the night down, plus a one-tap remediation hint ("Switch to planets tonight, deep-sky is compromised by the bright Moon"). TRENDING SKY EVENTS A built-in event ranker surfaces what is actually worth chasing this week — meteor peaks, lunar phases, planetary conjunctions, eclipses, ISS passes — ordered by visibility from your location, not by hype. COMMUNITY HOTSPOTS (OPTIONAL) See where stargazers around the world are heading right now. AsterScope quietly listens to public posts on Mastodon and Bluesky, extracts location signals for US, EU, and Japan dark-sky sites, and shows a ranked hotspot list. Tap any hotspot to open the original post in your browser — no third-party text is rendered inside the app. INTERACTIVE SKY CHART Real-time gnomonic projection backed by precise ephemeris. Tap any object for rise/set times, an altitude graph, and imaging suitability. Horizon-up mode mirrors what you see in the eyepiece. AR SKY OVERLAY Point your phone at the sky and AsterScope labels stars, planets, and deep-sky objects in real time. Markers stay pinned to celestial positions as you pan across the night. DARK-SKY FINDER Browse nearby dark-sky sites with Bortle ratings, compare light pollution, and plan trips to the best location within driving distance. OBSERVATION LOGBOOK Pin must-see objects to a Tonight List, work through them during the session, and keep a searchable log with year reports and CSV / Markdown export. BUILT FOR READABILITY Full Dynamic Type support across plans, events, logs, AR hints, and the dark-sky map — text scales cleanly with your iOS text size, including the larger accessibility sizes, with no clipping or overlap. WHAT YOUR APP PURCHASE INCLUDES The paid download already unlocks Tonight Score, the explainable plan, sky chart, AR overlay, dark-sky finder, observation log, weather forecasts, trending sky events, community hotspots, and the Core catalog (planets, the Moon, bright stars, and popular Messier objects). No subscription. No auto-renewal. OPTIONAL ONE-TIME CATALOG UPGRADES For deep-sky observers who want the long tail, two non-consumable, one-time upgrades extend catalog depth only: - Catalog Upgrade — adds Extended and Pro Deep Sky catalogs to planning, search, AR, and offline packs. - Ad-Free Catalog Upgrade — same catalogs, with no third-party ads. Neither is required to use the app. PRIVACY AsterScope uses coarse location only. Coordinates are rounded to a roughly 1 km grid before any third-party request. Apple WeatherKit, Open-Meteo, 7Timer ASTRO, and NASA GIBS receive only the rounded coordinates needed for forecasts and imagery. The community hotspot feature reads only public posts via official public endpoints (Mastodon, Bluesky), aggregates them on-device, and never uploads your location or identity. We do not collect or sell personal data. Full policy: https://qixiaobing54673.github.io/asterscope-site/privacy.html AsterScope works offline for core sky calculations. An internet connection is needed for weather, dark-sky site information, image fetching, trending events, and community hotspots.

About

Sky Map

Identify stars, constellations, planets, and satellites in real time by pointing your device at the sky. Explore celestial objects, track satellites, and discover what's visible tonight with AR overlays and time travel features.

Highlights
  • Real-time sky tracking with AR
  • Instant object identification
  • Augmented reality overlays
  • Time travel sky view
  • Satellite tracking (ISS)
  • Tonight's sky highlights
  • Night mode (red-light filter)
Features
Read full description

Explore the universe from your pocket with Sky Map – Star Tracker. Turn your iPhone into a powerful stargazing tool. Simply point your device at the sky to instantly identify stars, constellations, planets, and satellites in real time. Whether you're a beginner or an astronomy enthusiast, discovering the night sky has never been easier. KEY FEATURES Real-Time Sky Tracking Navigate the night sky with precision using AR technology. Watch stars and planets align exactly where they are above you. Instant Object Identification Tap any star or object to learn its name, distance, brightness, and more detailed information. Augmented Reality Mode Overlay constellations, star paths, and labels directly onto the live sky using your camera. Time Travel Sky Move forward or backward in time to see how the sky changes. Track planet movement and upcoming celestial events. Satellite Tracking Follow satellites like the ISS in real time and never miss a pass again. Tonight’s Sky Highlights Discover the best stars, planets, and constellations visible in your location tonight. Night Mode Protect your eyes with a red-light filter designed for comfortable night viewing. PREMIUM FEATURES Access thousands of deep-sky objects (galaxies, nebulae) Advanced zoom for telescope-like experience Smart observation lists Full event calendar (meteor showers, eclipses) Ad-free experience PERFECT FOR Stargazing beginners Astronomy lovers Students & educators Outdoor explorers WHY SKY MAP – STAR TRACKER? Accurate and smooth tracking Beautiful, modern interface Works offline Easy to use for all levels We currently offer the following auto-renewing subscription option: -$7.99 per month -$34.99 per month Payment will be charged to iTunes Account at confirmation of purchase. Your subscription will automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period. Your account will be charged for renewal within 24-hours prior to the end of the current period. Subscriptions may be managed and auto-renewal may be turned off by going to the Account Settings after purchase. No cancellation of the current subscription is allowed during active subscription period. • Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication, where applicable Terms of Use: https://tos.nguyenanhapps.com Privacy Policy: https://privacy.nguyenanhapps.com

Screenshots

AsterScope4 screens
Sky Map3 screens

Verdict

The call

The clearest difference is price: Sky Map at Free against AsterScope's $3.99. On update cadence, ads, in-app purchases 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

Sky Map is free to download; AsterScope costs $3.99 up front. AsterScope sells 2 one-off in-app purchases and Sky Map sells 3 in-app purchases, starting at $7.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

AsterScope ships an update monthly, Sky Map every 5 weeks. The most recent releases landed on September 29, 2026 and October 12, 2026 respectively.

Scorecard1 real difference · 9 level
AsterScope versus Sky Map: the parameters behind the verdict, then further details
ParameterAsterScopeSky Map
Price$3.99Free — better
Rating—1.0 (1 ratings) — better
Positive reviews—0.0% of reviews
Number of ratings—1 — better
Update frequencyMonthly — betterEvery 5 weeks
AdsNoNo
In-app purchasesYesYes
Monetization—Freemium
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.017.0
Further details — not scored
Size12 MB13 MB
Age rating4+4+
Developer红斌 戚Nguyen Anh

In-app purchases

2 purchases

AsterScope

One-time2
  • Catalog Upgrade$4.99
  • Ad-Free Catalog Upgrade$7.99
3 purchases

Sky Map

Subscriptions2
  • Sky Map Premium Monthly$7.991 Month
  • Sky Map Premium Yearly$34.991 Year
One-time1
  • Sky Map Premium Lifetime$49.99

Questions

Is AsterScope free?
AsterScope costs $3.99, and also offers in-app purchases.
Is Sky Map free?
Sky Map is free to download, with in-app purchases available.
Do AsterScope or Sky Map have ads?
Neither AsterScope nor Sky Map shows ads.
Which is updated more often, AsterScope or Sky Map?
AsterScope ships an update monthly, and Sky Map every 5 weeks. Most recently, AsterScope was updated on September 29, 2026 and Sky Map on October 12, 2026.

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