# KeyLight PRO > Off-camera flash photography exposure calculator and lighting modifier management tool. (iPhone/iPad app by Daniel Brewer.) - Source: https://appshunter.io/ios/app/keylight-pro/id635455188 (this page in markdown: same URL + `.md`) - Developer: [Daniel Brewer](https://appshunter.io/developer/635455211) - Category: Photo & Video, Productivity - Price: $0.99 - Rating: 3.70/5 from 3 App Store ratings · 9 written reviews indexed - Age rating: 4+ - Requires: iOS 10.0 · 3 MB - Languages: American English - Released: 2013-04-20 - Data updated: 2026-07-01 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/keylight-pro/id635455188/reviews.md ## What is KeyLight PRO? Shooting off-camera flash photography is challenging. Optimal exposure settings requires a knowledge of how to balance ISO sensitivity, aperture level, strobe power and strobe proximity to the subject. Because strobe power varies dramatically not only between manufacturers and models but also when external elements such as umbrellas, soft-boxes and lighting gels are used, quickly determining correct exposure settings can be challenging at best, and frustrating at the worst. KeyLight PRO removes all of this guesswork. Easy-to-use calculators quickly and clearly display optimal ISO levels, aperture settings, strobe power levels and strobe-to-subject distances in an intuitive, familiar interface. For the more advanced photographer, the Key Falloff calculator will calculate the proximity of the strobe from the subject in order to meet a desired exposure value falloff over a specific distance. For example, the area behind a subject is 10 feet away, should be 3 stops underexposed relative to the subject, and the strobe is firing at 1/4 power and the camera is at ISO 400. What should the aperture setting be on the camera? With KeyLight PRO, the answer is a tap away. How many strobes does KeyLight PRO support? The Virtual Gear Bag provides an unlimited number of strobe makes, models and settings, and the Strobe Library provides over 100 pre-loaded strobe model configurations. The Gear Bag is readily accessible on all of the calculators, providing quick, easy and accurate exposure settings when swapping between your strobes. Only using one strobe? Keep multiple "set ups" in your Gear Bag under a variety of configurations: bare bulbed, gelled, soft-boxed, umbrellaed, neutral-density filtered, wall-bounced, go-bo'd. There is no limit to the number of ways the light from a single strobe can be modified. Create as many configurations for these light modifiers as you need, and know in an instant how to most effectively utilize them. KeyLight PRO. Control the light. ## Key features - Exposure calculators (ISO, aperture, strobe power, distance) - Key Falloff calculator - Virtual Gear Bag for unlimited strobe configurations - Strobe Library with 100+ pre-loaded models - Support for various light modifiers - Save multiple setups ## Chart rankings - #194 in Top Paid · Photo & Video (US App Store) ## Recent user reviews (9 of 9) All indexed reviews: https://appshunter.io/ios/app/keylight-pro/id635455188/reviews.md ### 5/5 — Works Great! *2022-01-05* Running great on the iPhone 13 Pro MAX, and assists me in numerous occasions when it comes to photography setup in various situations. Not sure what the iPhone 12 guy is talking about- he’s probably very confused on how to open an application without a home button? I could even help him it’s that easy, but he may lack the mental fortitude to understand how to press buttons? I certainly have enjoyed the app and its complex calculations. ### 1/5 — Does not work on iPhone 12 *2021-11-03* This app does not work on iPhone 12 and I fully intend to demand a refund and have my credit card refused to charge. ### 2/5 — It works in meters only once and stop *2020-04-22, version 8.0* Whatever the value I choose the App don’t show me in meters and the flash power shows the limit of 1/64, my flash works until 1/128. ### 3/5 — Good app, but ... *2019-11-09* Would’ve given 5 stars if it was possible to set power level down to 1/256 as many strobes offer this level of power adjustment. Otherwise, perfect app. ### 1/5 — Valores em metrô não funciona *2018-07-25, version 8.0* Não consegui os valores em M somente em ft 😑😑😑😑😑😑 ### 3/5 — Update? *2017-06-21, version 7.0* Update? ### 5/5 — Wonderful app *2016-11-14* I would love to see an option to select flash power divided into 1/3 or 1/2 Thank you for making this app. This makes the guesswork from film much easier. ### 5/5 — Works great! *2014-08-13* This is exactly what you need if your off-camera manual flash doesn't assist in these calculations. This takes the guess work out of determining flash to subject distance, aperture, or power. Just enter your flash's guide number and you're good to go. Thank you! ### 5/5 — Better than expected *2013-06-14* Very handy for pre-planning a major shoot. ## Frequently asked questions about KeyLight PRO ### What is KeyLight PRO? KeyLight PRO is a photography app designed to simplify off-camera flash exposure calculations. It provides tools to determine optimal ISO, aperture, strobe power, and distance, making flash photography more accessible. ### How does KeyLight PRO help with exposure? It features intuitive calculators that remove the guesswork from balancing ISO, aperture, strobe power, and proximity to the subject. This ensures you achieve the desired exposure settings quickly and accurately. ### Can KeyLight PRO handle different lighting setups? Yes, the Virtual Gear Bag allows you to store an unlimited number of strobe makes, models, and settings. You can also manage various light modifier configurations like gels, soft-boxes, and umbrellas. ### What is the Key Falloff calculator? The Key Falloff calculator helps advanced photographers determine the necessary strobe proximity to achieve a desired exposure value falloff over a specific distance, useful for controlling background exposure. ### What devices does KeyLight PRO support? KeyLight PRO is available for iPhone and iPod devices, as indicated by its supported devices list. ### How much does KeyLight PRO cost? KeyLight PRO is a paid application, priced at $0.99. There are no in-app purchases or subscriptions mentioned. ### Does KeyLight PRO have ads? No, KeyLight PRO does not contain advertisements. It is a paid app with no ads, providing an uninterrupted user experience. ### When was KeyLight PRO last updated? The latest version of KeyLight PRO was released on August 10, 2017. The app was initially released on April 20, 2013. ## Version history (last 3 releases) ### 8.0 — 2017-08-10 This update from Apple will improve the functionality of this app. No new features are included. Updated for iOS 10+ ### 7.0 — 2014-02-07 A cleaner, more intuitive interface and quicker, more convenient feature access. ### 2.0 — 2013-04-20 No release notes. ## Apps similar to KeyLight PRO | App | Rating | Price | Category | | --- | --- | --- | --- | | [Spot Meter Pro](https://appshunter.io/ios/app/spot-meter-pro/id1558581037) | 4.4 (13) | $4.99 | Photo & Video | | [WorkPlace - Film Crew](https://appshunter.io/ios/app/workplace-film-crew/id6449962780) | — | $4.99 | Photo & Video | | [f/ Tools](https://appshunter.io/ios/app/f-tools/id668237473) | 3.7 (6) | $4.99 | Photo & Video | | [FilmMeter](https://appshunter.io/ios/app/filmmeter/id6753060069) | 5.0 (41) | Free | Photo & Video | | [Manual Flash Calculator](https://appshunter.io/ios/app/manual-flash-calculator/id6739006004) | — | $2.99 | Photo & Video | | [Flash Photography Adviser](https://appshunter.io/ios/app/flash-photography-adviser/id1354932744) | 5.0 (2) | $0.99 | Photo & Video | --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-01.*