It's Thursday morning and I've just downloaded my resting heart rate data for the past year. On Monday, I wrote about what that trend actually means — and got a question that's been nagging me ever since: what apps are there? Where do they come from? How many people use them, and do they really make a difference?
That was a good question. So now we dig.
It started with the pedometer
The history of health apps doesn’t begin with a smartphone. It begins in Japan, in 1965, with a pedometer called the Manpo-kei — the “10,000 step counter.” The number 10,000 wasn’t scientific, it was marketing. But it stuck in the collective consciousness and lives on today in every health app on the market.
When Apple's App Store opened in 2008 with 500 apps in total, there were already rudimentary fitness apps. Fitbit launched its first wristband in 2009. Strava arrived in 2009, MyFitnessPal back in 2005 — as a website, long before smartphones dominated. It was the era of the hobbyist: enthusiasts who logged their workouts in spreadsheets finally had a better option.
Then came the phone sensors. Accelerometer, GPS, heart rate sensor, oxygen measurement. And everything changed.
The big players — and their numbers
Apple Health
Introduced in 2014 as a built-in platform in iOS 8. Not an app you download — an infrastructure that collects data from all other apps and devices. No official user figures are published, but with 2.3 billion active Apple devices globally, it's reasonable to assume that Apple Health is the most widely used health platform in the world by installed base. It measures heart rate, sleep, ECG, oxygen saturation, and now generates AI-based health insights. It's the hub of the ecosystem — everything else feeds into it.
Google Health / Fitbit
Fitbit launched in 2007 as a hardware company, acquired by Google in 2021 for $2.1 billion. The platform has now been rebranded as Google Health and equipped with a Gemini AI-powered health coach for energy levels and recovery predictions. Dominant on Android, strong in Asia and parts of Latin America where iPhone penetration is lower.
Strava
Started in 2009 in San Francisco by two Harvard students who wanted to share their rowing sessions. Today, it's something completely different. In April 2026, Strava passed 195 million registered users and is adding three million new ones per month. Of all devices, mobile is the most common — 72 percent of Strava users record workouts directly in the app. Garmin comes in second, Apple Health third. It's no longer just for cyclists and runners — walking is on the rise, and Gen Z is leading that trend.
MyFitnessPal
Founded in 2005, sold to Under Armour in 2015 for $475 million, resold in 2020. 200 million registered users and 85 million monthly active users make it the world's largest food tracking app — with a food database of over 14 million products. Now with AI coaching built in.
Garmin Connect
Garmin's own ecosystem, tightly coupled to their hardware. Approximately 45 million active users, but with a hardware base that is growing rapidly — 42 percent increase in fitness revenue in the first quarter of 2026. Garmin is the engineers' choice: in-depth data, long battery life, no compromises.
Oura Ring
Finnish company, founded in Oulu in 2013. The ring that sits on the finger and measures HRV, sleep stages, body temperature and recovery 24/7. No public user figures, but Oura is now considered one of the leaders in the global fitness ecosystem and is widely used by researchers, athletes and sleep-optimized technology consultants worldwide. Integrates with Strava, Apple Health and Google Fit.
WHOOP
Boston-based company founded in 2012. No screen, no pedometer — just continuous HRV, sleep, and recovery tracking, with a subscription-based band. Popular in elite athletes and people who take recovery seriously. WHOOP and Oura have brought “readiness scores” and HRV tracking into the mainstream.
HealthifyMe
India's answer to MyFitnessPal, founded in Bangalore in 2012. Strong AI coach with a focus on South Asian food and diet — a database that Western apps have never been able to build. Dominant in India, growing in the Middle East and Southeast Asia.
Integrations — the nerve fibers of the ecosystem
The interesting thing isn’t what each app does on its own — it’s how they talk to each other. Apple Health acts as a hub: apps like Vora integrate with over 500 platforms — Apple Watch, Garmin, Oura Ring, WHOOP, Fitbit, Samsung — and read and write data to Apple Health automatically in the background. 
Google Health now connects with Apple Watch, Garmin, Samsung Galaxy, Whoop, and Oura via Health Connect on Android and Apple Health on iPhone. 
This means that a person's health data effectively flows freely between hardware and platforms — if you allow it. Your run on Garmin shows up in Strava. Your sleep score from Oura influences your workout recommendations in WHOOP. Apple Health brings it all together in one place.
It's an ecosystem. Not an app.
What is measurable globally — and what does it tell us?
The fitness tracker market is expected to reach $9.2 billion in revenue by 2026, with a user penetration of 12.6 percent globally.  That sounds small — but that’s one in eight people on Earth with a health app actively in their pocket.
Over 100 million people use popular fitness apps daily, and the top ten apps account for more than 60 percent of all downloads globally. 
Strava publishes an annual report on its entire user base — combined, it's one of the world's largest exercise datasets. You can see which cities run the most, which countries cycle the most, what time of day people exercise. It's real-time exercise research, conducted by 195 million volunteer participants.
The health app industry was worth $3.5 billion in 2025 — a 23.5 percent increase in one year.  It’s growing faster than most other app segments.
Are you really researching this?
Yes — and the results are clearer than you might think. In a systematic review of 69 digital health platforms for chronic diseases, patients in 77 percent of the studies reported that the digital tools improved their quality of life, health, and ability to manage their illness independently. 
Research published in the Journal of Medical Internet Research 2025 indicates that AI-assisted and app-based technologies are transforming preventive medicine — from responding to disease to preventing it, through personalized risk assessment and continuous follow-up. 
It's a paradigm shift. The doctor sees you once a year. Your clock measures you 24 hours a day, 365 days.
What no one talks about
Data is power — and it goes both ways. Both Strava and Fitbit collect about 21 unique data points per user.  Apple is more restrictive about what leaves the device, but exceptions exist.
There’s also an affordability gap that’s rarely discussed. An Oura Ring costs around €300. The Apple Watch Ultra 2 costs more than €1,000. The most accurate measurements are reserved for those who can already afford to live healthily. India is the fastest-growing market, with 16.5 percent annual growth  — but free versions of apps are the norm there, not premium subscriptions.
Technology is democratizing health awareness. But it is not democratizing access to the best technology as quickly.
What happens next?
The best apps of 2026 no longer think in silos — they weave together exercise, nutrition, and mental health into a single view. Sustainability features like carbon footprint calculations and nature-based exercise challenges are starting to emerge. And solutions tailored for people over 50 — with low-intensity movement, accessible interfaces, and a focus on recovery — are growing rapidly.
The last point is worth dwelling on. Those of us who are not 25 and training for competition — we are actually the biggest market of the future.
I measure my resting heart rate every night with the Apple Watch Ultra 2. Last Monday, I shared a full year of data — what it means, how to interpret it, and why the trend is more important than the number. Read that post if you want the context for all of this.
And you — what app do you use?Has it changed anything for you?