A lot of people are reading these articles:

• How do I cancel my Jumbo subscription?
• iOS IAP Cancellation Information
• How do I delete my Jumbo account?
• What features are offered for each subscription option?
• Can my subscription be shared across multiple devices?
• Refund Request Information
• How does Jumbo's free trial work?
• Android IAP Cancellation Information
• I already have a Jumbo Subscription, how do I restore it?
• Can I change my device and still access my Vault contents?