Original photos from an iPhone
OurChest stores the file the iPhone uploads. It does not run a second compression pass for the Chest.
An iPhone can share a photo as a file rather than as a chat preview. OurChest stores that file. It does not make a smaller copy for the Chest.
If you edited the photo before sharing, the phone may upload the edited file. OurChest keeps what it receives. It does not recover an earlier version from the camera roll, and it does not add a location field.
The iOS app is not in the App Store yet. Until it is, this page describes the product, and it does not start a download.