Comparison

Thoughtful vs FastFlow

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

Head to head
About

Thoughtful

A private digital journal designed for reflection and thought organization. It offers a clean interface and simple tools to capture and revisit your experiences, with all data securely backed up via iCloud.

Highlights
  • Private journaling space
  • Thought capture and organization
  • Effortless reflection tools
  • Clean iOS aesthetic
  • Daily page structure
  • iCloud data backup
Features
Read full description

Thoughtful is a private space to ponder, write, and reflect. It’s designed to help you capture your thoughts, organize them effortlessly, and revisit them with clarity over time. Every feature is built with care and informed by research on how people process their experiences and memories. The goal is simple: make it easy to record what matters and return to it later. The design follows a clean, native iOS aesthetic paired with simple writing and organization tools, so you can capture thoughts quickly and without friction. Each day lives on its own page, creating a lightweight, structured space that reflects the patterns of daily life. All data is backed up by iCloud, and no one at Thoughtful can read what you write. No account, email, or credit card is required either.

About

FastFlow

Features
Read full description

FastFlow turns intermittent fasting into a guided, personalized journey — and it reads your Garmin's biometrics in real time so you can actually see your fast working. Connect a compatible Garmin watch and FastFlow maps your fast through six metabolic stages — Fed, Clearing, Shifting, Burning, Cleansing, Renewing — using your live heart rate, HRV, Body Battery, and stress. Instead of a plain timer, you see what's happening inside your body, and what to do at each stage. WHY FASTFLOW - Live biometrics, not just a clock. Your Garmin data drives the ring, so every stage is grounded in what your body is actually doing. - Know what to do, hour by hour. Each stage suggests the right activities — sleep through the early hours, deep work and fasted training in Burning, rest in the long stages. - A smart end-of-fast review. Log how the fast went in two taps; FastFlow reviews it against your own baseline, entirely on your device. - Break your fast the right way. A guided, step-by-step refeeding flow with gentle food suggestions — plus a shop for break-fast staples like bone broth and electrolytes. - Build the habit. Streaks, a color-coded calendar of your fasts, and per-stage insight. LIVE ACTIVITY + DYNAMIC ISLAND Track your fast from the Lock Screen and Dynamic Island — the stage and elapsed time stay current at a glance. PRIVATE BY DESIGN FastFlow has no account. Your fasting and health data is processed on your device and stored in your own private iCloud. We don't collect, sell, or share it. REQUIRES A GARMIN Live biometric sync requires a compatible Garmin watch with the FastFlow watch app (available on the Garmin Connect IQ Store). You can also use FastFlow phone-only: start/stop fasts, follow the stage journey, log break-fasts, and keep your history. FASTFLOW PREMIUM A subscription unlocks live Garmin biometric sync, full history and insights, and Live Activity. - Monthly and annual plans, with a free trial. - Payment is charged to your Apple ID at confirmation of purchase. - Subscriptions renew automatically unless turned off at least 24 hours before the end of the period. - Manage or cancel anytime in your App Store account settings. - Terms: https://fastflowapp.com/terms - Privacy: https://fastflowapp.com/privacy FastFlow is a general wellness and fasting-tracking app. It is not a medical device and does not provide medical advice, diagnosis, or treatment. Any biometric data shown comes from your own consumer fitness wearable and is for general wellness information only. Always consult your doctor before making any medical decisions, starting a fast, or changing your health routine.

Screenshots

Thoughtful4 screens
FastFlow4 screens

Verdict

The call

The clearest difference is in-app purchases: Thoughtful at none against FastFlow's 2. FastFlow's advantage is iOS requirement (16.4 vs 18.0). On price, ads 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. FastFlow sells 2 in-app purchases, starting at $4.99 per month. Thoughtful asks for nothing beyond the download.

Scorecard2 real differences · 8 level
Thoughtful versus FastFlow: the parameters behind the verdict, then further details
ParameterThoughtfulFastFlow
PriceFreeFree
Rating5.0 (5 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings5 — better—
Update frequencyEvery 2 weeks—
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhoneiPhone
Requires iOS18.016.4 — better
Further details — not scored
Size10 MB3 MB
Age rating4+4+
DeveloperBrian Lu ChangDaSecure Solutions LLC

In-app purchases

None

Thoughtful

No in-app purchases

2 purchases

FastFlow

Subscriptions2
  • Monthly$4.991 Month
  • Annual$39.991 Year

Questions

Is Thoughtful free?
Thoughtful is free to download, with no in-app purchases.
Is FastFlow free?
FastFlow is free to download, with in-app purchases available.
Do Thoughtful or FastFlow have ads?
Neither Thoughtful nor FastFlow shows ads.

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