I have it in APX mode (it shows up in device manager as "APX"), and I'm wondering: is there any way to boot a boot.img so I can get it up and running again, or is my device a lost cause?
To my understanding no, you need a device specific backup made ahead of time.
See this thread
So unfortunately in your case you are more than likely out of luck, and for everyone else I would suggest make a backup now and store it on PC just in case
Good news is we should see a new nexus tablet in the next month or so...
|Thread Tools||Search this Thread|