Hey @ericwuu 
Thanks for the post and cool idea! Unfortunately, I’m not aware of a native way to do this in Bubble. I’m sure it could be done with a custom plugin, but it might require a wrap service that lets you capitalize on a more in depth integration with the mobile phone your app is running on.
As it stands, the closest you could get outside of going the custom plugin / wrapper route would be to build in a multi file uploader where you instruct your users to take their photos outside of the app and then they can absolutely select and upload multiple photos at a time.
That being said, I would love to be wrong on this and we’re constantly amazed by what our users have built on Bubble. It’s certainly possible something exists that could enable this sort of functionality without having to put together something custom.
Either way, best of luck with the build and don’t hesitate to reach out to us directly with any additional questions. You can email us directly at Support@Bubble.io