Sunfollower vs Gx FoCalc
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Sunfollower
Visualize sunrise, sunset, and sun direction for any day and location. Features an interactive AR view to calculate sun positions and provides twilight times, elevation, azimuth, and shadow ratios.
- Sunrise and sunset position tracking
- Interactive Augmented Reality view
- Civil, nautical, astronomical twilight times
- Sun elevation and azimuth
- Shadow ratio calculation
Read full descriptionHide full description
Sunrise, sunset and sun direction for any day at any location. Key features: - Instantly see how sunrise and sunset positions change throughout the year - Interactive Augmented Reality view screen. Tap on the screen and the application will calculate when the Sun is at that position. - Civil, nautical, astronomical twilight times - Elevation and azimuth of the Sun - Shadow ratio Notes: Maps require data connection. Please ensure that Compass calibration in the System Settings on your device is switched ON. The app will work more accurately with it. The Compass accuracy can be affected by magnetic or other environmental interferences.
Gx FoCalc
Easily calculate the 35mm equivalent focal length and apparent aperture for various camera sensor sizes and lens configurations. Input your focal length, aperture, and any focal reducers or teleconverters to see the full-frame equivalent.
- 35mm crop factor calculation
- Equivalent focal length
- Apparent aperture calculation
- Supports focal reducers
- Supports teleconverters
Read full descriptionHide full description
FoCalc by [Gx]Ace Is the internet's best 35mm Crop Factor Calculator. Ever wonder what the 35mm equivalent of a 23mm f2 on APS-C would be? Ever wonder what that 120mm f8 8x10 lens would be if it were put in 35mm terms? Well now you can know it all with FoCalc! FoCalc allows you to input a focal length and aperture as well as a focal reducer or teleconverter and automatically calculates the equivalent focal length and apparent aperture on 35mm Full Frame.
Screenshots
Verdict
The clearest difference is price: Gx FoCalc at Free against Sunfollower's $2.99. Gx FoCalc also leads on rating (4.9 vs 4.1) and update cadence (daily vs every 4 months). Sunfollower's advantage is iOS requirement (10.0 vs 17.5). 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
Gx FoCalc is free to download; Sunfollower costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Gx FoCalc holds the better App Store score, 4.9 against 4.1. Both are backed by a comparable volume of ratings — 12 and 7 respectively. Written reviews point the same way: 70% of Sunfollower's written reviews are positive against 100% of Gx FoCalc's.
Sunfollower ships an update every 4 months, Gx FoCalc daily. The most recent releases landed on October 26, 2026 and October 24, 2026 respectively.
| Parameter | Sunfollower | Gx FoCalc |
|---|---|---|
| Price | $2.99 | Free — better |
| Rating | 4.1 (12 ratings) | 4.9 (7 ratings) — better |
| Positive reviews | 70.3% of reviews | 100.0% of reviews — better |
| Number of ratings | 12 — better | 7 |
| Update frequency | Every 4 months | Daily — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 10.0 — better | 17.5 |
| Further details — not scored | ||
| Size | 22 MB | 0 MB |
| Age rating | 4+ | 4+ |
| Developer | Evgeny Vostrikov | Casey Cavanaugh |
Customer experience
Sunfollower
Gx FoCalc
In-app purchases
Sunfollower
No in-app purchases
Gx FoCalc
No in-app purchases
