What is the ruling on using an application that prevents phone use and imposes a financial penalty for opening it before the set time?

The "Digital Detox" application is an app that blocks access to phone applications for a specified period, allowing the user to exclude certain apps. If the user wishes to unblock access before the set time, they must pay a sum of money to the app developers. It appears that this money is not a fee for using the free app, but rather a type of commitment that the user imposes upon themselves to prevent phone usage. This penalty clause is permissible, and the general rule for conditions is their validity, as Al-Bukhari narrated from Shuraih regarding someone who voluntarily stipulated a condition upon himself. The Islamic Fiqh Academy has permitted penalty clauses in all financial contracts, except for contracts where the primary obligation is a debt, as this would constitute explicit usury.