I shared my app with my co-worker and I would know if he could export data from object or to download app's .qvf on his laptop so that he can modify the app.
In the current version is not possible for your colleague to download your apps. You can however send it by any other means (e.g. email, dropbox, ftp etc.)
If interested watch this video to learn more on full local app sharing with Qlik Sense Desktop:
Qlik Sense Desktop - Sharing Apps (video)
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