It depends on whether you're on Server, Data Center or Cloud and the length of your subscription.
For Data Center and Cloud, these are monthly (Cloud only) or annual subscriptions, which you can choose not to renew to cancel them.
For Server, apps are purchased on a perpetual licences and renewals are only for support and maintenance. That means you would keep the app forever but lose access to their support team or new updates which might be released.
To see how pricing works for each host type:
Atlassian's marketplace partners have had a very productive start to 2021! Since our last roundup, our developer community has added over 160 new cloud apps to the Atlassian Marketplace to help you...
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