User-agent change with the introduction of iPadOS 13
On September 24, 2019, Apple is scheduled to release iPadOS 13 which changes the default user-agent for the iPad Air 2 and newer iPads. This will impact how related iPad tablet user activity appears in Google Analytics “Audience > Technology > Browser & OS” reporting. It will be associated with device category desktop as opposed to tablet.
Previously all iPad user activity would show up as associated with Browser “Safari” and Operating System “iOS”. As of this change, user activity from supported iPad devices will be associated with Operating System “Macintosh”. This change will cause a decrease in iPad tablet traffic and an increase in Safari desktop traffic reported in Google Analytics.
Reference:
https://support.google.com/analytics/answer/3223194#user-agent