Like most developers, I've always known that building accessible web apps is the right thing to do, but I wasn't sure how to do it. I tried my best to add image descriptions and audio transcripts and figured that was good enough. Then I started work on a Django 1.8 project for an agency that has a low-vision website administrator. When we sat her down in front of the app's admin interface for the first time, she had a lot of trouble using it. The contrast was way too low, and control features like sort by column weren't properly labeled. After watching her navigate the admin interface and learning more about how disabled users navigate the web, I customized our app's admin interface to improve accessibility. I've since gotten training in web accessibility, and want to share some of what I've learned so we can all build more accessible apps.