Microsoft has released an updated and fixed version of the Remote Desktop Client for iOS 10.0 for iOS. The latest release’s version number has been incremented to 10.1. The release notes contain no mention of what has been fixed and the changelog is exactly the same as the previous version. Microsoft has not publicly disclosed what the bug was in the previous release. BleepingComputer has asked Microsoft to confirm what the fixed issue has been, but has not heard back at this time.
Source: https://www.bleepingcomputer.com/news/microsoft/microsoft-remote-desktop-client-for-ios-is-back-after-bug-fixes/