A cleaner solution (than the one given by Ankit Goyal) that fixes Simulator logs without affecting Device logs is available at https://stackoverflow.com/a/39651073/1033581:
- Under Product > Scheme > Edit Scheme... > Run, set the OS_ACTIVITY_MODE environment variable to ${DEBUG_ACTIVITY_MODE} so it looks like this:
- Go to your project build settings, and click + to add a User-Defined Setting named DEBUG_ACTIVITY_MODE. Expand this setting and Click the + next to Debug to add a platform-specific value. Select the dropdown and change it to "Any iOS Simulator SDK". Then set its value to "disable" (Xcode 8) or "default" (Xcode 9) so it looks like this:
