I have a tcp system with connection mode = dialog, idle timeout = 2000 and answer timeout = 5000
This system works good on iPad, iPhone and iViewer for Android 4.0.191 but doesn't work on iViewer for Android 4.0.195 . Sometimes I can send one command but no more, the behavior changes depending on background network option.
You can check with this little project attached. Use Hercules on computer to simulate tcp system..