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My organisation maintains multiple applications and there's a confusion about how the APNs keys are supposed to be used.We are using firebase to send push notifications.So far we have two keys for two different applications. But cannot create a third. This question on StackOverflow indicates that we're supposed to use the same key for all applications.My questions are:If we only can create two keys is one supposed to be used for production and one for testing/development?If we use the same keys for multiple unrelated application (unrelated except that the apps are all created by the same organisation) what stops cloud messages from being pushed to the wrong application?Are we supposed to create a convention to circumvent the problem of sending messages to the wrong app?For example: * using topics with a prefix for each app? * create device groups, one for each app?Relevant firebase documentation