Happy to help you with MacDive if you go that route. I realize this can all be confusing, because "dive log" is a standard term for where you log your dives, but there's also a product called "Dive Log." The key point is that there are various products to log your dives that will download from your Teric and sync between your Mac and iPhone. Only thing you NEED the Shearwater app for on your iPhone is to update the Teric's firmware. Historically, the dive computer manufacturers have offered software that will sync with their dive computers, but their software has never been nearly as good as the software from third party developers. Shearwater is particularly good at working with third party developers to allow them access to the computer data for logging.