What you (and only you) decide to upload, then goes to Cloud Storage and Gemini. So the only provider your photos are shared with is Google.
But the honest part is that the data is not end-to-end encrypted. In transit and at rest, yes, but I run the project, so technically I can look. I don't and I have special machinery around my processes so that I never do this unintentionally, but that's still a promise. Do you think this would be a blocker for potential app users? What can I do if the on-device processing is not an option?
About costs. It's subscriptions, nothing else. Free tier stops at 20 captures, Pro is $9.99/month (for US, different for other countries). Processing itself is very cheap (a small fraction of a cent per photo).
Thanks!