Bubble Level + Compass Pro vs SynScan
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Bubble Level + Compass Pro
This utility app provides a precise spirit level and compass for your iPhone and Apple Watch. Get live readings on your wrist, even when your phone's screen is out of sight. Features include bullseye, horizontal, and vertical levels with 0.1-degree precision.
- Bullseye, horizontal, and vertical levels
- 0.1-degree precision
- True and magnetic heading
- Apple Watch companion app
- Gyro or accelerometer sensor mode
- Red-light night mode
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Bubble Level + Compass Pro combines a precise spirit level, compass, and Apple Watch companion app, so when your phone is placed somewhere hard to see its screen, you can still get live readings from your wrist. No more out-of-reach setups, and no more crouching. Features: • Bullseye level plus horizontal and vertical levels with 0.1 degree precision • Bubble level units: Angle (degrees) or Incline/Slope (%) • True and magnetic heading with direction text • Magnetic declination • Apple Watch companion app • Gyro or accelerometer sensor mode • Gyro calibration offset to compensate for camera bulge or uneven phone cases • Pitch/Roll/Yaw rotation rate readouts • Compass calibration status • Red-light night mode The tool is normally included in my astronomical app (Polar Scope Align Pro), but I decided to release it as a separate app because I could not find anything with the features I wanted on the app store. (A free ad-supported version is also available)
SynScan
Control motorized telescope mounts for celestial object tracking and exploration. Features include GOTO functionality, object catalogs, and gamepad navigation. Ideal for novice users with alt-azimuth mounts.
- Control telescope mount slew, align, GOTO, and track
- Point and Track celestial objects
- Support gamepad navigation
- Browse and save celestial object catalogs
- Third-party app integration (ASCOM, SkySafari, Stellarium)
- Emulator mount for testing
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Use the SynScan app to control Sky-Watcher telescope mounts via Wi-Fi or Bluetooth LE. Mounts without built-in Wi-Fi can be supported via a SynScan Wi-Fi adapter. This version of the SynScan app is suited for novice users using alt-azimuth mounts. Features - Control telescope mount to slew, align, GOTO and track. - Point And Track: track celestial objects (including the Sun and planets) without aligning. - Support gamepad navigation. - Browse a catalog of stars, comets, and deep sky objects. Or, save your own objects. - Provide access to mount for use by third-party apps, including ASCOM clients, SkySafari, Luminos, Stellarium Mobile Plus, Stellarium Desktop or customer-developed apps. Also set up mount alignment for Luminos, Skysafari. - Support access to the mount and the SynScan app from any platform that supports TCP/UDP connections. - Provide emulator mount for testing and practicing. - Track fast-moving earth satellites by working with the PreviSat app on Windows PC or the Lumios app on iOS devices.
Screenshots
Verdict
The clearest difference is review sentiment: Bubble Level + Compass Pro at 100% against SynScan's 22%. Bubble Level + Compass Pro also leads on rating (5.0 vs 3.3) and iOS requirement (12.0 vs 14.0). SynScan's advantage is price (Free vs $0.99) and update cadence (every 2 months vs every 17 months). On ratings volume, 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
SynScan is free to download; Bubble Level + Compass Pro costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Bubble Level + Compass Pro holds the better App Store score, 5.0 against 3.3. Both are backed by a comparable volume of ratings — 22 and 8 respectively. Written reviews point the same way: 100% of Bubble Level + Compass Pro's written reviews are positive against 22% of SynScan's.
Bubble Level + Compass Pro ships an update every 17 months, SynScan every 2 months. The most recent releases landed on September 10, 2026 and June 1, 2026 respectively.
| Parameter | Bubble Level + Compass Pro | SynScan |
|---|---|---|
| Price | $0.99 | Free — better |
| Rating | 5.0 (22 ratings) — better | 3.3 (8 ratings) |
| Positive reviews | 100.0% of reviews — better | 22.2% of reviews |
| Number of ratings | 22 — better | 8 |
| Update frequency | Every 17 months | Every 2 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Devices | iPhone, iPad, iPod, Apple Watch — better | iPhone, iPad, iPod |
| Requires iOS | 12.0 — better | 14.0 |
| Further details — not scored | ||
| Size | 7 MB | 46 MB |
| Age rating | 4+ | 4+ |
| Developer | Dimitrios Kechagias | Astropower Technology Co. Ltd. |
Customer experience
Bubble Level + Compass Pro
SynScan
In-app purchases
Bubble Level + Compass Pro
No in-app purchases
SynScan
No in-app purchases







