Note, that there are two LuckGrib apps, one on iOS and one on macOS. Purchase one, or both, of the applications through the appropriate App store, linked above. LuckGrib on macOS and iOS are separate purchases.
Note, that once you have purchased LuckGrib from the App store, that all future updates to the application on that platform are free.
Note that the app download itself is free. After downloading LuckGrib, on the Mac, iPad or iPhone, you will then be presented with an opportunity to start a 14 day free trial of the app. This is done through a free in-app purchase.
There are currently three in-app purchase products available, each with a 14 day free trial:
Weather data access. Purchasing this product gives you access to the app itself, and the ability to download and import weather data.
Offshore Data gives you access to weather data while offshore, via the Iridium GO! or RedPort Optimizer. Before you purchase this product you must have already purchased weather data access.
Weather Routing gives you access to the advanced, optimized weather routing system. Before you purchase this product you must have already purchased weather data access.
Your purchase of LuckGrib is tied to your AppleID. Once you have purchased any of the LuckGrib products, that purchase can be shared, on the same platform with your other devices.
For example, if you purchase LuckGrib on an iMac, it can be used on a laptop you own if it uses the same AppleID. Also, if you purchase LuckGrib on an iPhone or iPad, it can be used on another iPhone or iPad, if it is using the same AppleID.