In Strategy Mobile 9.x and 10.x, for report or document that does not have cache enabled, this "Cache real-time data" feature is used to accelerate the online experience by pre-caching the documents that the user will likely request during the session.
This mobile configuration setting "Cache real-time data" will force Strategy Mobile Client to use local caches (downloaded by the pre-cache feature) even if the document has caching disabled. The idea is to define a time window that will determine whether the local cache is still valid. The purpose of this time window is to avoid “expiring” the cache too soon. The setting would be a timer that specifies for how long these caches are considered as valid.
When the checkbox is checked, the default value is 300 seconds (5 minutes)

To enable real-time cache, there is a setting on Report and Report Services Document level:

Note: This feature is already present in Strategy iOS Mobile 9.x and 10.x