It's built with SwiftUI on iOS and Jetpack Compose on Android, both sitting on top of a shared C codec and renderer (also compiled to WebAssembly for the website). PHP/MySQL for the backend, and S3/CloudFront for storage.
Every new use starts with a game that includes one of my previous drawings. Yes, that's really me (I get lots of folks writing 'Are you an AI?'). Depending on what I'm up to, it may take me a bit to respond to drawings. I do store my drawings so I can re-send them to different users as I get LOTS of drawings per day and drawing a new one each time would leave me with no time left to work on anything else.
App Store: https://apps.apple.com/app/hankydoodle/id6754983889 Google Play: https://play.google.com/store/apps/details?id=com.hankinsoft...
The forever guess mode also was a late addition, mainly added it because my daughter was enjoying guessing more than drawing.
When she got home from school, she would grab my phone and guess all of the initial rounds that I hadn’t got to yet and leave the drawing to me. So I built that mode for people who didn’t feel like drawing at the time, but also works as a gap filler for folks with no active games.