Lumen Calculator vs RabattHUD
Price, ratings, monetisation and update history for both apps, side by side β with what reviewers say about each.
Lumen Calculator
This physics and math tool quickly converts between lumens, lux, and candelas. It provides instant calculations with copyable results and includes reference formulas. Optimized for everyday use, it supports high precision and various units.
- Instant calculation
- Copyable results
- Reference formulas
- High precision (16 decimal places)
- Supports various units
- Ad-free and private
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The Lumen Calculator is a physics/math calculator designed to swiftly and easily convert between lumens, lux, and candelas. Features: - Instant calculation. - Results are copyable to other apps. - Formulas included as references. - Supports up to 16 decimal places. - Supports various units for each input. - Works seamlessly on both iPhone and iPad. - Lightweight, compact app optimized for everyday use. - Ad-free and built with privacy in mind. Definitions: - Lumens: Unit of luminous flux, representing the total amount of light emitted by a source. - Lux: Measure of surface illumination, indicating how much light is received by a surface. - Candelas: SI units of luminous intensity, representing light emitted from a source in a particular direction per steradian. Note: Candelas measure the light emitted in a specific direction, while lux measures the light received per unit area. One steradian, the area of the receiving surface, is equal to the squared distance between the source and the receiver. Formulas: 1. Lumens = Candelas * Ξ© (For a specific angle) 2. Lumens = Candelas * 2Ο * [1 - cos(ΞΈ/2)] 3. Lux = Lumens / Area 4. Lux = Candela / DistanceΒ² Where: Ξ© = 2Ο * [1 - cos(ΞΈ/2)] Ξ© = 4Ο Thanks for your support, and please visit nitrio.com for more apps for your iOS devices.
RabattHUD
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This discount calculator not only calculates the discount on an existing price quickly, he also comes in an extremely futuristic HUD design as is known from science fiction movies. Some elements are also animated, which makes this discount calculator even cooler. Impress your friends with this app if you look like a time traveler from the year 3,001 at the next sale in the shopping center who calculates the discount. Simply enter the discount in percent and the starting price. This App will give you the final price that you have to pay at the checkout. It also shows the money you have saved. You can also share the discount with your friends via WhatsApp etc. or save it as an image on your mobile phone. Maybe you want to print it out? Of course, the app is completely ad-free and there are no in-app purchases or subscriptions. Pay once, always use. If that's not a fair deal, we donβt know what to do :-)
Screenshots
Verdict
The clearest difference is price: RabattHUD at Free against Lumen Calculator's $2.99. RabattHUD also leads on update cadence (every 2 months vs every 27 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.
Scored on Price Β· Rating Β· Positive reviews Β· Number of ratings Β· Update frequency Β· Ads Β· In-app purchases Β· Monetization Β· Best chart rank Β· Devices Β· Requires iOS
RabattHUD is free to download; Lumen Calculator costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Lumen Calculator ships an update every 27 months, RabattHUD every 2 months. The most recent releases landed on August 22, 2026 and June 10, 2026 respectively.
| Parameter | Lumen Calculator | RabattHUD |
|---|---|---|
| Price | $2.99 | Free β better |
| Positive reviews | 0.0% of reviews | β |
| Update frequency | Every 27 months | Every 2 months β better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | β |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 13 β better | 13.2 |
| Further details β not scored | ||
| Size | 1 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | Nitrio | Marc Martin |
In-app purchases
Lumen Calculator
No in-app purchases
RabattHUD
No in-app purchases
Questions
Is Lumen Calculator free?
Is RabattHUD free?
Do Lumen Calculator or RabattHUD have ads?
Which is updated more often, Lumen Calculator or RabattHUD?
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