Rallytap (formerly "Down") is a mobile app that lets you tap a button to see which of your friends are free to hang out. Instead of sending dozens of texts to figure out plans, you can get the gang together in a single tap.
At it's peak, Rallytap became a popular way to organize pickup sports, impromptu dinners, and movie nights. It even took over a California high school. We were featured several times in the press: 'Down' cofounder Michael Kolodny: 'Being with other people makes you happier'
We built the initial version of Rallytap for iOS in about a week and a half in Swift. For our API we used Django, and for our chat feature, we used Firebase. Firebase's cost quickly became an issue as more users started chatting concurrently. To combat that cost, we decided to switch to using a custom Meteor server.
Our users were telling us that we needed an Android version so that all their friends could take part in their group chats. With only myself and my co-founder Andrew, we didn't have the manpower to keep up our rapid iterations while maintaining two separate codebases. So we decided to rebuild the app using the newly production-ready Ionic.
While Ionic's performance wasn't quite as a fast as our native app, it was surprisingly close. We used Angular as our frontend framework, and a DDP client to talk to our Meteor server. After the switch, thanks in part to Ionic's hot code pushes, our pace of development skyrocketed. Overall, we were super happy with the switch.