Life Cycle has an optional Premium subscription, that costs $9.99.
Should you choose to subscribe to Life Cycle Premium, the purchase will be charged to your iTunes account. You can manage or cancel your auto-renewable subscription by entering the user settings in iTunes after the purchase. The subscription will be auto-renewed 24 hours before the subscription period ends, with the same kind of subscription you already bought, to the same price. It's not possible to abort the subscription during the time it's active.
By accessing any of Life Cycle's Premium features, you'll be asked to upgrade if you want to continue. Just follow the instructions if you want to upgrade, and you'll be ready for the Premium experience in no time.
For the moment, the Premium features are Online Backup (found under Settings), Trends (found at the bottom row in the main interface) and Sleep Quality results on your locations and events (found in the Trends section).