Shopify's app billing cycles
Make sure that you consider app billing cycles when you plan to uninstall an app. Recurring app charges are generated the first time an app charge is approved, and then on the first day of an app's billing cycle. Because of this, a charge will appear on your bill even if you uninstall an app only a day or two after you install it.
Recurring app charges are billed with the next Shopify 30-day invoice. In the example below, the bill on May 5 includes the app subscription that overlaps from April 20-May 20. The bill on June 4th similarly includes the app subscription from May 20-June 19 (since May has 31 days).
If you stop paying your bills, or close your store, then Shopify freezes your account and your recurring app charges. If you start your payments again, or re-open your store within 30 days, Shopify unfreezes your account and your recurring app charges resume.
If you pause your store using the Pause plan, you don't need to uninstall your apps. Your recurring app charges are frozen while your store is on the Pause plan, but the charges resume automatically when you reopen your store, or if your store is upgraded to the Pause and Build plan.
For more information see Shopify's app subscriptions documentation.