I have implemented a login item as I was recommended in this post. In the helper app I launch the main app using NSWorkspace method launchApplication:showIcon:autolaunch:, sending YES to autolaunch parameter.
The problem is in following: I need to check if the applications was autolaunched not to show start tooltip. The only variant I found is [[NSUserDefaults standardUserDefaults] boolForKey:@"autolaunch"], and it returns NO always.
The problem could be solved using launch arguments - but sandbox, unfortunately, cuts them too.
Is there something I missed?