I am having a problem with your Android app not syncing when my Note 4 is in sleep. I have confirmed that my wifi connection remains active at this time. (Auto-sleep setting on, 30 mins.) I have tested by adding a file on either end and waiting for more than 30 minutes with phone in sleep, no sync. If I reboot the phone or open the app on my phone, sync occurs immediately. I have tried moving the sync folder on my phone from SD card to Device, no difference.
If I turn Auto-sleep off, syncing works as it should without having to open the app or reboot. I would really prefer the Auto-sleep setting on - any ideas for a work around?