Native smartphone Fitness App Development

Building a minimalist, data-friendly fitness app that respects user privacy

May 11, 2024 - Willem L. Middelkoop

As a little side-project, squeezed between my normal work, I have been working on something of personal interest: a native workout tracking app for iOS. I wanted to make my smartwatch obsolete, instead using my phone to track workouts. How hard could it be to gather detailed sensor data using native Swift APIs?

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Apple Watch workout app shows large buttons to start a workout - no need for additional configuration

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Screenshots of the app's onboarding process: asking for permissions and guiding new users

I got some magic in my pocket: The app tracking workouts from the background - during recordings it just shows a widget on the homescreen

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Articles (159)

2025-02-10 Better Laptop
2025-01-27 Podcast Downloader
2025-01-23 Champions League of Webdesign
2025-01-18 Master of Change
2024-12-19 Data versus Feeling
2024-12-09 The Problem With Bitcoin
2024-11-11 Write your own words
2024-11-10 Go Viral on X
2024-10-20 Marathon
2024-09-10 I see dead people
2024-05-11 Developing a native iOS app
2024-03-24 Half Marathon
2024-03-05 No, I Won't Build That!
2024-02-16 Vision Pro
2024-01-16 Health and fitness data
2023-12-15 Backup Rotation Scheme
2023-11-10 Apple Watch as Phone
2023-11-01 And... there is light!
2023-10-14 Giving AI Training
2023-10-13 Hello, stranger
2023-08-23 The Same, Differently
2023-05-31 Impact of training
2023-05-08 Tablet as Tool
2023-05-03 Using AI to generate code
2023-05-01 Working Offline First
2023-04-20 Tips for Long-Distance Cycling
2023-04-05 Cutting Cloud Costs
2023-02-08 Back to the University
2022-12-22 Rolex DateJust 36
2022-11-01 Moving to the countryside
2022-10-23 MUSE in Carré
2022-09-15 The Ultimate Freedom Bike
2022-09-11 Computer says no
2022-07-30 CAPTCHA Alternative
2022-07-17 Offline Music
2022-04-18 Snake '97 High Scores
2022-01-14 Wearing WHOOP 4.0
2021-12-09 For the love of mini
2021-11-19 Escaping the flat tires
2021-10-25 Using Google Free Android
2021-09-30 Inspiration from a child
2021-08-31 Protecting VMware ESXi
2021-07-13 The birth of a child
2021-06-30 Migrating to the Cloud
2021-06-05 Wearing Grand Seiko
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2021-05-04 Hospitalised with MCADD
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2021-03-26 Art of visualisation
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2019-11-26 Supernova E3 Pro 2 dynamo powered headlight
2019-11-22 Building a professional 72TB NAS
2019-10-19 Flying in a C47-A (DC-3) classic plane
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2019-09-27 Visiting an international hackers conference
2019-09-10 Fighting backscatter spam at server level
2019-08-28 Riding with a power meter on your bike
2019-08-18 Creating a minimal road bike
2019-07-16 Limitations of sleep tracking using a wearable
2019-07-15 Optical vs chest strap heart rate monitors
2019-06-25 Assembling a cargo bike
2019-06-24 Six months with MCADD
2019-05-29 Solo around the Markermeer (211KM)
2019-05-24 Dig for dummies
2019-04-30 The best bike computer app: Cyclemeter
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2019-03-20 Servicing a robot vacuum cleaner
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2019-01-29 Born with MCADD
2019-01-24 My first weeks as dad
2018-12-22 Business in a bag
2018-12-06 Do amazing things with a focused mind
2018-11-16 Around town in an electric car
2018-11-02 Is the Apple Watch the modern tool watch?
2018-10-16 Rescuing files from a broken harddisk
2018-10-09 Using a budget Android as main smartphone
2018-09-27 Swimming and cycling with Apple Watch
2018-09-26 Optimising images for the web and performance
2018-08-21 Space travelling from El Teide
2018-08-20 Google Analytics vs AWStats
2018-07-20 Helping people with free software
2018-07-10 Enjoy a festival without alcohol
2018-06-09 Removing paint from a bike frame
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2018-05-09 Lunch by plane
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