The project I'm currently on involves writing an app that will share most state management/business logic (we're very lightly using/abusing Redux for that part)

The project I'm currently on involves writing an app that will share most state management/business logic (we're very lightly using/abusing Redux for that part) and a web API client in Javascript (well, Typescript) across phone (iOS, Android), tablet (ditto), and TV (tvOS, Fire-whatever, maybe AndroidTV if that turns out to be easy), using React Native for the UI on everything but tvOS (TVML there). I also thew the logic/state/HTTPclient part of the app behind a crappy Electron "desktop" UI the other day for giggles. Wasn't hard, took about half a day. No design or releasable GUI in that amount of time, but you can click buttons and fill in values and stuff happens, using the same code as all those other platforms do (or will, in some cases—it's ongoing). So you can't share the GUI, but you can share pretty much everything else. > (and possibly easy on the battery). React Native's not too bad, compared to other cross-platform whatevers that have come before it. Electron kind of almost flirts with being easy on the battery at its very best, but hell, no-one else seems to care about that so why should you? > creating and drawing on top of PDFs too Oh god. Have fun with Android and PDF. Yeesh. [EDIT] I should add that you can always add native code to React Native projects for parts that need it. Not sure about Electron, but... maybe?