Cupertino's new dev rules restrict apps that drain the battery, put unnecessary strain on an iPhone's or iPad's resources, and cause the fancy gadgets to generate excessive heat.
Moreover, Apple is also barring apps from crypto mining activity done within the device.
Another section of Apple's App Store review guidelines allows apps to mine for cryptocurrencies only if the process is performed off the device. This could give Apple grounds to remove the Onavo app, although the software is still available despite the rules kicking in last week.
Calendar 2 was then pulled from the App Store and relaunched without the mining element. These, Apple writes, "must come from established banks, securities firms, futures commission merchants, or other approved financial institutions and must comply with all applicable law".
Four years ago, Apple removed every single bitcoin wallet application on its App Store, including popular wallet app Blockchain. In a dedicated cryptocurrency section, the company goes on to break down in more detail what is - and, crucially, is not - permissible. While this particular adjustment may not seem to be a developer-friendly move at first glance because of its restrictive nature, it will actually be a boon for devs who create apps that offer cryptocurrency transactions. Cryptocurrency apps can't offer users virtual coin for tasks like downloading other apps, getting other users to download the app, or boosting social media activity.