Overview

PhotoStats.io was my first personal mobile app: a quantified self app to track, visualize, and learn from your photo data. Every photo on your phone carries metadata (when, where, which camera, and much more). PhotoStats collected it, kept a record even after photos were deleted or you changed phones, and turned it into simple stats and charts. I built it in React Native and released it for both iOS and Android in late 2017.

What I did

• Came up with the idea and did 25 customer interviews before designing and building v1
• Built v1 in React Native: photo counts over time, weekly stats, and full CSV or JSON export (over 200 columns of EXIF data per photo)
• Added machine learning auto-tagging in v2, to help classify what’s in your photos
• Used it on my own life: maps of a year of travel, when I take photos, and what I take them of, written up in What Do Your Photos Say About You? and A Year in Data: 2018
• Gave a talk, “How I Built a Photo Tracking App with React Native,” at a Singapore JS meetup in January 2018

What I learned

• Photo metadata turned out to be a surprisingly rich record of a life. The location data alone mapped out where I’d been all year.
• Launching my own mobile app had been on my goals list for a couple of years. After building plenty of client apps, it felt good to finally ship one of my own (2017 annual review).