To upgrade your current subscription to an annual subscription, follow these steps:
For iOS:
From the Chatbooks app, tap into the My Books tab and click into your subscription.
From there, tap into the Settings found in the upper right-hand corner.
Tap "Manage subscription."
Under "Billing Cadence" tap "Billing Frequency"
Tap the "Pay Annually" option
Be sure to tap Save and then Done
For Android:
From the My Books tab in your Chatbooks app, tap into your subscription.
From there, tap into the Settings found in the upper right-hand corner.
Tap "Manage subscription."
Under "Billing Cadence" tap "Billing Frequency"
Tap the "Pay Annually" option
Be sure to tap Save and then Done
Learn how to upgrade to an annual subscription from Chatbooks.com here.