Google Nexus 7 3G free storage not recognised by Play store I have 85% free space of my 32 GB internal storage (there is no external sd card on this device), and yet I cannot download any new app or even update an old one, because Google Play Store keep telling me there is not enogh free space.
I am running Aopk ROM, tilapia-userdebug 4.2.2 JDQ39
I've been getting this error a lot lately (stock N7 16gb), too, and I have plenty of room on my device. Usually I can go back in and tell it to update and it will work the second time.

Just now I was getting an update message on an app and when I went in to update it there was no update option. I wonder if this is related to the new Google Play version coming out. 

I went to Google Play on my laptop and told it to update the app and it worked that way.

You might try downloading the apk for the new Play Store and see if that helps.