Peak Flow Log vs Peak Flow Diary | Asthma
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Peak Flow Log
This app helps you monitor your asthma and peak flow readings. It uses a color-coded system to indicate the quality of your measurements. Additional features are available through a premium version.
- Track asthma and peak flow
- Color-coded value indicators
- Premium features available
- Feature requests welcome
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Simple app to track your asthma / peak flow. A colour indicates how good your value is. More features are avaliable with Peak Flow Log Plus. More features are planned. Feature requests are welcome!
Peak Flow Diary | Asthma
Easily record daily peak flow values and visualize breathing changes with clear graphs. Understand your asthma trends, identify early warning signs, and support your health management. Useful for medical visits and daily care.
- Daily peak flow recording
- Easy input methods (slider/keyboard)
- Zone-based graph display
- Record list with memo management
- Cloud storage and account support
- Intuitive and simple operation
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Understand Your Breathing, Every Day. Peak Flow Diary is an easy-to-use app that helps you record your daily peak flow readings and track changes in your breathing over time. With just a few seconds of recording each day, you can better understand: • Your usual breathing condition • Changes and trends in your breathing • When your condition starts to worsen Color-coded zones make it easy to see your current breathing status at a glance, helping you manage your respiratory health every day. 【Key Features】 ■ Quick and easy daily recording Record your peak flow in seconds using either the slider or keyboard input. Choose the method that works best for you. ■ Color-coded graphs View your peak flow readings in easy-to-read graphs. Color-coded zones help you quickly understand your current condition and identify trends over time. ■ History and notes Review all your previous records in one place. You can also save notes about your symptoms, activities, or daily events. ■ Medical Report (PDF) Automatically generate a PDF medical report from your recorded data. Print it or show it on your smartphone to help explain your condition during medical appointments. ■ Reminder notifications Set reminders so you never forget to record your peak flow. ■ Secure cloud backup Your records are safely stored in the cloud, making it easy to restore your data when changing devices. ■ Simple and intuitive design Designed to be easy to use every day, so you can build a lasting habit. 【Premium】 Unlock additional features to gain deeper insights into your breathing. ■ Breathing Monitor Analyzes your daily peak flow readings and sends push notifications when sudden drops or declining trends are detected. ■ Long-term analysis View your peak flow data over an entire year to identify long-term trends that may not be visible within just 28 days. ■ Comparison graphs Compare your current data with the previous year to better understand seasonal changes and long-term patterns. ■ Extended Medical Reports Generate PDF medical reports covering up to one year of recorded data. ■ Ad-free experience Enjoy the app without advertisements. Keeping a daily record is the first step toward better understanding your breathing. Start tracking your breathing today with Peak Flow Diary. Peak Flow Diary Terms of Service https://susatthi-asthma-diary-prod.web.app/terms-of-service.html?lang=en Peak Flow Diary Premium Terms of Service https://susatthi-asthma-diary-prod.web.app/terms-of-service-premium.html?lang=en
Screenshots
Verdict
The clearest difference is ads: Peak Flow Log at none against Peak Flow Diary | Asthma's shown. Peak Flow Log also leads on review sentiment (100% vs 74%) and rating (5.0 vs 4.7). Peak Flow Diary | Asthma's advantage is ratings volume (36 vs 1) and iOS requirement (15.0 vs 26.2). On price, update cadence, in-app purchases and monetization model 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
Both are free to download. Peak Flow Log sells 1 one-off in-app purchase and Peak Flow Diary | Asthma sells 2 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.
Peak Flow Log holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Peak Flow Diary | Asthma has 36 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 100% of Peak Flow Log's written reviews are positive against 74% of Peak Flow Diary | Asthma's.
Peak Flow Log ships an update every 2 weeks, Peak Flow Diary | Asthma every 3 weeks. The most recent releases landed on October 10, 2026 and October 27, 2026 respectively.
| Parameter | Peak Flow Log | Peak Flow Diary | Asthma |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (1 ratings) — better | 4.7 (36 ratings) |
| Positive reviews | 100.0% of reviews — better | 74.2% of reviews |
| Number of ratings | 1 | 36 — better |
| Update frequency | Every 2 weeks — better | Every 3 weeks |
| Ads | No — better | Yes |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 26.2 | 15.0 — better |
| Further details — not scored | ||
| Size | 5 MB | 57 MB |
| Age rating | 4+ | 4+ |
| Developer | Friedrich Ewald | Keyber Inc. |
Customer experience
Peak Flow Log
Peak Flow Diary | Asthma
In-app purchases
Peak Flow Log
- Peak Flow Log Plus$0.99
Peak Flow Diary | Asthma
- Monthly Plan14 Days trial$3.991 Month
- Annual Plan14 Days trial$24.991 Year
Questions
Is Peak Flow Log free?
Is Peak Flow Diary | Asthma free?
Which has better reviews, Peak Flow Log or Peak Flow Diary | Asthma?
Do Peak Flow Log or Peak Flow Diary | Asthma have ads?
Which is updated more often, Peak Flow Log or Peak Flow Diary | Asthma?
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