Working with new collaborator

I’m a little uncomfortable asking this - so I’m working on the basis that there is no such thing as a stupid question (please!!!).
Obviously, in order to create my first Tropy project, I downloaded the Tropy app and then added the images material. I now want to share my efforts with a collaborator.
If I send them a copy of my folder which contains both the Tropy file and all the linked images, can they simply open the Tropy file by double-clicking on it - or do they need to download the Tropy app first in order for the file to work?

your collaborator needs to download the Tropy app in order to work the project.

Thanks. Now I can sound like I know what I’m talking about!

One more question, please: when I send the collaborator the material (and they have downloaded Tropy) do they just double-click on the .tpy file (and the file will hunt for the Tropy app) or do they need to drag the file on to the Tropy app icon? They will be using Windows.

After the installation on Windows, Tropy should start automatically. You can then drag the .tpy file to the window to open it. Tropy should also register itself as the default app for .tpy files during the installation, so yes, double-clicking the file should open the project as well.

In addition to the previous answers, there’s a brief section in the user documentation on collaboration: Collaboration - Documentation. It’s a good idea to know what is and isn’t possible when sharing a project.