DayDayCookDayDayCook

The iPhone/iPad universal application is the core of the DayDayCook iOS experience. As team lead, I led development efforts on the app’s custom video player, recipe page, ecommerce homepage, and many other features.

The video player supports picture-in-picture so users can keep watching while scrolling through recipes, quick sharing, recipe step overlays, synchronized recipe step alert popovers, a shortcut button to enter the comments section, and a fully customized user interface. The recipe page includes ingredients, cooking steps, recommended recipes, tips, and comments. The app also hosts flash sales and extended sales sections with countdown timers, with WeChat Pay and Alipay integrated for checkout. The app includes a unique profile page with custom UI components, and interactive features like photo competitions and surveys.

DayDayCook sold video cooking courses through the app using Apple’s in-app purchase system. Each course was priced individually, and once purchased, the video lessons and associated recipe content were permanently unlocked for that user.

We built a livestreaming feature as an ecommerce channel — live video broadcasts used to sell products and advertise for brand partners. At peak, the feature handled thousands of simultaneous live connections and thousands of comments per minute. The core challenge was keeping the app stable and responsive on low-memory devices under that sustained load while maintaining smooth video playback and real-time comment rendering.

The recipe detail page was the core of the app and a constant target for new features — header, ingredients, cooking steps with images, recommended recipes, ecommerce listings, user comments, and more. The same page was reused for events and other content types that shared some sections but not others, and certain sections were absent in specific regions.

Originally a single monolithic ViewController, it grew increasingly difficult to maintain. Calculating section offsets was fragile when sections could be conditionally absent, and any change risked breaking scroll positioning or section visibility across the different content configurations.

The page also pulled data from multiple services, so responses arrived at different times. Without proper diffing, this caused two failure modes: displaying inconsistent intermediate states while waiting on slower responses, and reloading the entire view when a new response arrived — causing the page to jump even when only one section needed to be inserted or refreshed.

I re-architected it as a modular section tree: sections contain sub-sections, all the way down to individual views, each self-contained and responsible for its own sizing. The tree could be diffed, so when new data arrived only the affected sections were inserted or updated — the rest of the page stayed stable. It also eliminated a whole class of crashes from data source and collection view inconsistencies, since the diffing handled batch updates correctly. This eliminated the global offset calculations, made sections trivially addable or removable, and extended naturally to complex sub-layouts — ingredient rows, for example, had previously required manual height calculation across the whole section.

The architecture proved general enough that we adopted it for every collection and table view in the app, significantly reducing bugs and engineering churn. The approach turned out to be independently similar to IGListKit, which was under development around the same time.

To support DayDayCook’s offline retail expansion, I led development of an iPad point-of-sale application deployed across 10+ physical stores. The app handled customer sign-up, cooking class purchases — with WeChat Pay and Alipay integrated for payment — and class attendance tracking, so store staff could see which classes a customer had purchased and how many sessions remained.

The iMessage app and sticker app launched alongside iOS 10 with App Store featuring in Hong Kong, Taiwan, and mainland China. I created both applications independently in the week before iOS 10’s release.

The app supports recipe sharing via iMessage, a sticker application with unlockable rewards for the 2017 Chinese New Year promotion, keyword and extended search functionality, and shopping list sharing. Shared recipes launch the main DayDayCook app directly to the specific recipe video. The instability of the beta iOS 10 versions and the requirements for split screen support in both landscape and portrait orientations created difficulties, but we delivered a highly performant application.

As part of the global launch in 2016, I developed the Apple TV app independently using a combination of Objective-C and JavaScript. The app was featured on the front page of three App Stores—China, Hong Kong, and Taiwan.

The app opens to the full library of over 3,000 DayDayCook recipes, sorted by category. It supports full text search, user login including via Facebook, and synchronizes each user’s favorite recipes with the iPhone and iPad apps. Each recipe has a details page with video, cooking steps, ingredients, and a favorite button. All recipe videos can be played full screen on the Apple TV.

The Apple Watch app was my first major independent project at DayDayCook. I spent one month collaborating with Apple’s App Store team to build an application featuring DayDayCook recipes optimized for the smartwatch display.

The app opens to a rotating carousel of the five most recently published recipes. Users can swipe right to access favorite recipes saved through the main application. The primary challenges involved managing image sizing within the watch’s undocumented memory constraints and designing creative workarounds for limited UI elements like scrollviews and pull-to-load-more functionality.