Free Trial Period
Start: The day you install the app.
Duration: 14 days.
Example: If you install on July 1st, your free trial ends on July 14th. (inclusive of start & end date)
Billing Cycle
Starts: The day after your free trial ends.
Duration: 30 days.
Billing Date: The first day of the billing cycle.
Example: For an installation on July 1st:
Free Trial: July 1 - July 14.
First Billing Cycle: July 15 - August 13 (billed on July 15).
Second Billing Cycle: August 14 - September 13 (billed on August 14).
Deduction of the subscription fee
First Charge: After the free trial, on the first day of the billing cycle.
Recurring Billing: Charges recur every 30 days from the end of the free trial, and the fee is deducted on the first day of every billing cycle.
for reference, check out shopify's article on app charges by clicking the button below.