What you need:

• Github desktop https://desktop.github.com/
• Visual Studio code https://code.visualstudio.com/

• nodejs https://nodejs.org/en/

  Quick start thing (I /think/ this will work):

  1. download github desktop
  2. Fork this repo.
  3. clone the forked repo (green button, open in github desktop)
  4. install nodejs
  5. open a terminal, navigate to the folder where you saved the code, run npm install
  6. install visual studio code
  7. continue with the stuff below

  If necessary, configure visual studio code if it complains about not being able to find 'git':

  1. open settings (ctrl+shift+p type 'settings') and open user settings, search for 'gitcommand' and click the edit icon next to it, then paste the path to git, something like: "C:/Users//AppData/Local/GitHubDesktop/app-1.0.9/resources/app/git/mingw64/bin/git.exe"

https://facebook.github.io/react-native/docs/getting-started.html under the tab "Building Projects with Native Code"

for windows: set up so that you can build the android app

for macos: set up so that you can build the android and/or ios apps