It's in the app store for real, now: https://play.google.com/store/apps/details?id=org.andrewpuglionesi.com.routinetimer

This is a timer app for keeping track of repeated routines with both timed and untimed steps. I've decided to target individuals undergoing physical therapy, because it's what I designed and battle-tested the app for (and what I use it for almost every day). Physical Therapy Timer is a cross-platform app written in NativeScript (Angular/TypeScript, XML, CSS).

iOS is not a possibility at the moment because Apple essentially requires you to have an iPhone and/or Apple computer to test and publish an iPhone app, and I don't intend to spend a couple thousand bucks on those anytime soon (no offense to Apple lovers).

Note: I don't recommend NativeScript. I would go for Ionic or React Native (they're more popular and have larger communities) or simply native development; my experience with this framework has not been ideal. Particularly challenging when writing a mobile app in JavaScript/TypeScript is trying to accomplish things at the operating-system level. I think NativeScript will work fine if you're just interfacing with a database, but it can become much harder than native development when you want to interface with the device's hardware and its unique capabilities.