Share your app code as an .aia file that can be loaded into App Inventor and remixed:
Choose File | Export selected project (.aia) to my computer to export the source code (blocks) for your project. The source code downloads in an .aia file.
If you send it to a friend, they can open it with File | Import selected project from my computer.
One tip! Some email systems will reject .aia files, so it is better to link to your files on an online drive.