An open-source Android COVID-19 tracking app built using core UI components from the Robinhood stock trading app. The app displays key metrics around the growth of coronavirus, including the number of positive cases, negative cases, and deaths per day. The data for our app comes from The COVID Tracking Project. Google Play does not allow COVID apps from non-medical sources, so I had to publish it in an alternative app store, F-Droid, which is for free and open source software: https://f-droid.org/packages/edu.stanford.rkpandey.covid19tracker/. I also turned this app into an 8-part YouTube tutorial, true to my philosophy of repurposing my work as much as possible :) The YouTube tutorial did fairly well since both COVID and Robinhood were top of mind when I published the app last year.

I made this Android app for educational purposes to show the integration with 3 different Firebase services (Authentication, Cloud Functions, and Firestore). You're able to update your status using only emoji, and you can see the status of every other user in the app, along with a timestamp. It's a fun, cute way to play with emoji and try to interpret what other people mean. I also made a 6 part YouTube series explaining how to build the app and how all the pieces fit together. This tutorial is a great choice if you want to learn how to integrate your app with Firebase. Interestingly, the app has organically taken off in the Play Store with more than 50K installs, but people are unhappy with the limited functionality. Despite putting [TEACHING] in the title, and adding a disclaimer in the description, I usually get a 1 star review every week 😂 If I had more time, it would be interesting to make a more useful version of this app.

An Android app that gives you simple and clear explanations for data structures and algorithms. I built the initial version of this in 2012 which was fully native, but it was too painful to update the content since it required deploying a new APK. So in 2017, I did a v2 of Algorithm Helper (this app) which is essentially a wrapper around a webview. The content is coming from a blog I created using Jekyll, a popular static site generator: https://rkpandey.com/AlgorithmHelper/. The idea was that anyone could then add their own article to Algorithm Helper by contributing to the open source repo. I had a vision for this to become the Wikipedia of algorithm knowledge, with intuitive explanations that people could access on their Android app. That didn't quite work out 🤣 Honestly, the reason I made an Android app instead of *just* a web blog is because I wanted to capitalize on Google Play search, which is far less competitive than web search (way fewer apps compared to websites). The results back this up: I haven't touched this app in years, but it has 10K+ installs, and a few people download the app every week. It also has a surprisingly good rating, 4.4 stars on 48 ratings, for an app which I haven't touched in ages.

I built an Android version of the classic memory game we've all played. By default, you have to find pairs from a set of predefined images on various board sizes (4x2, 6x3, or 6x4). The special twist to the game is that you can customize the memory cards by having each image be a picture on your phone. These images get uploaded to Firebase Storage, and you can share the unique identifier for your game with anyone in the world. Thus the name "My Memory" :) This app has around 700 installs and 172 active devices. However, what I'm more proud of is the resulting 20 part video series on my YouTube that I made explaining how to build it. To get people interested, I offered to pay for people's Google developer fee ($25) if they followed the tutorial and built the app. This led to at least 15 clones of this app on the Play Store. Some examples: https://play.google.com/store/apps/details?id=com.gmail.chauhanparth86.mymemory and https://github.com/ZiyueQian/MyMemory.