Comparison

Lumen vs CoolFirePD

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

Head to head
About

Lumen

Gain control of your metabolism with real-time insights and personalized nutrition plans. This app helps you understand if your body is burning fats or carbs, offering guidance on what and when to eat for weight loss and a healthier lifestyle.

Highlights
  • Real-time metabolic insights
  • Personalized daily nutrition plans
  • Lifestyle recommendations
  • Healthy habit building
  • Progress tracker
  • Monthly cycle tracker
  • Community support
Read full description

Do you want to take control of your metabolism, lose weight, and live a healthier lifestyle? With Lumen’s personalized metabolic coach, you can! Lumen is the world’s first device to measure whether your body is burning fats or carbs - in a single breath. Say goodbye to guessing and hello to real-time metabolic insights, tailored daily nutrition plans, and recommendations on what to eat and when. With direct access to your metabolism at your fingertips, our features will guide you to speeding up your metabolism, keep you motivated to reach your health goals, and feel your best self. EVERYTHING YOU NEED TO HACK YOUR METABOLISM Features include: * Real-time metabolic insights to guide you on your journey * Personalized daily nutrition plans * Lifestyle recommendations for sleep, exercise, fasting, and more * Customizable tracks to achieve your goals * Healthy habit building * Progress tracker * Monthly cycle tracker * An engaged community for support and discussions This app integrates with Health apps to sync data on your activity and sleep. SUITABLE PLANS FOR EVERYBODY At Lumen, we believe in a personalized approach to health. That's why we offer different plans designed to fit your unique goals, whether it's weight loss, fitness performance, or improving your metabolic health. With our progress tracker and healthy habit influences, you'll have the support you need to succeed. WORKING ON YOUR WEIGHT LOSS JOURNEY By macro-tracking your meals, you can continue enjoying the meals you love with a new outlook and healthier relationship with food and yourself! PERSONALIZED NUTRITIONAL PLANS & MEAL PLANNING Lumen tracks your metabolism, but it’s also a powerful tool for managing your journey in nutrition, fitness, and overall well-being. The app includes interactive features to help you stay on track with your nutrition goals, such as meal planning and recipe suggestions. FUELING UP PRE AND POST WORKOUTS Don't let energy levels hold you back from your workout goals. Lumen gives you real-time insights into your body's fuel usage, so you'll know exactly when to hit the gym and when to rest. Lumen levels will guide you on whether you have enough energy or need to fuel up before your workouts. SCIENTIFICALLY-BACKED If you like talking science - we’ve been featured in peer-reviewed articles and building research ourselves. Lumen's technology has been scientifically proven to accurately measure metabolic fuel usage when compared to the gold standard (RER) for measuring metabolism in multiple validation studies. PREMIUM CONTENT Improve your knowledge with our informative library of videos from fitness experts, coaches, and nutritionists. MOTIVATION Every breath measurement will tell you what’s happening in your body. These insights help you maintain your motivation and give you guidance on how to hit your goals. So, what are you waiting for? Download Lumen today and start your journey to a healthier, happier you! You'll have the support and guidance you need to take control of your metabolism and live your best life. Lumen has been featured in Forbes, BBC News, TechCrunch,Entrepreneur.com, Wired Magazine, Shape Magazine, and more Winner of the CES 2019 Best Reviews Award | Listed in the Top 30 Best Devices CES 2019 | Esquire 2020 product award Please note: You must have a Lumen device to use this app. You can order your device from www.lumen.me While Lumen is not intended as a medical device, it is recommended to consult your doctor before starting any nutrition plan. Interested in partnering with us? Get in touch with us www.lumen.me/partners Join us and begin your Lumen journey today!

About

CoolFirePD

This app works with a compatible pedometer to track your daily steps, calories burned, and other health metrics. It seamlessly syncs this data with your device's health platform for a comprehensive overview of your activity.

Highlights
  • Step counting
  • Calorie tracking
  • Health data synchronization
  • Activity monitoring
  • Pedometer pairing
Read full description

Paired with CoolFire Pedometer to measure your steps, calories etc and sync with health data

Screenshots

Lumen4 screens
CoolFirePD4 screens

Verdict

The call

The clearest difference is review sentiment: Lumen at 73% against CoolFirePD's 0%. Lumen also leads on rating (4.6 vs 1.0) and ratings volume (6.5K vs 2). CoolFirePD's advantage is monetization model (free vs free with in-app purchases) and update cadence (every 5 days vs fortnightly). On price, 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Lumen holds the better App Store score, 4.6 against 1.0. That said, the two scores are not equally well evidenced: Lumen has 6.5K ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 73% of Lumen's written reviews are positive against 0% of CoolFirePD's.

UpkeepUpdate frequency

Lumen ships an update fortnightly, CoolFirePD every 5 days. The most recent releases landed on November 1, 2026 and October 24, 2026 respectively.

Scorecard5 real differences · 5 level
Lumen versus CoolFirePD: the parameters behind the verdict, then further details
ParameterLumenCoolFirePD
PriceFreeFree
Rating4.6 (6.5K ratings) — better1.0 (2 ratings)
Positive reviews73.0% of reviews — better0.0% of reviews
Number of ratings6.5K — better2
Update frequencyFortnightlyEvery 5 days — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPodiPhone, iPod
Requires iOS15.0 — better15.6
Further details — not scored
Size270 MB56 MB
Age rating12+4+
DeveloperMetaflowNew York Standard Watch Company, LLC

Customer experience

Lumen

All ratings6,541 ratings
Positive92.9%
Neutral2.0%
Negative5.1%
Written reviews707 reviews
Positive73.0%
Neutral7.4%
Negative19.7%

CoolFirePD

Written reviews2 reviews
Positive0.0%
Neutral50.0%
Negative50.0%

Bugs and requests

Lumen

Reported bugs

3 issues
  • App crashes and freezes
  • Difficulty calibrating the device
  • Inaccurate breath measurement detection

Requested features

4 requests
  • Ability to edit logged foods and measurements
  • Integration with fitness and food tracking apps
  • More flexible and personalized carb recommendations
  • Improved meal planning and recipe suggestions

CoolFirePD

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Lumen

No in-app purchases

None

CoolFirePD

No in-app purchases

Questions

Is Lumen free?
Lumen is free to download, with no in-app purchases.
Is CoolFirePD free?
CoolFirePD is free to download, with no in-app purchases.
Which has better reviews, Lumen or CoolFirePD?
Lumen is rated higher. Lumen averages 4.6 out of 5 from 6.5K ratings, while CoolFirePD averages 1.0 from 2 ratings.
Do Lumen or CoolFirePD have ads?
Neither Lumen nor CoolFirePD shows ads.
Which is updated more often, Lumen or CoolFirePD?
Lumen ships an update fortnightly, and CoolFirePD every 5 days. Most recently, Lumen was updated on November 1, 2026 and CoolFirePD on October 24, 2026.

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