Lenovo Tab 2 a7-10F storage issue

Hi, I have a lenovo Tab 2 a7-10F (running on Android Kitkat 4.4.2). After installing some apps on the device I have now encountered a storage problem. Everytime I try to download anything from Google Play it just gives me an "insufficient storage available" error. I have about 490MB of free storage on my tab right now but I still cannot install any app in it. When I download apps from other markets like Aptoide, they install perfectly but Google Play refuses to install or even update any app - no matter how small- unless I free up more than 500MB of space. I cannot move apps to my 16GB external SD card as the device has an 'emulated' storage and does not read obb files stored on my external SD. The following are the steps I've tried so far-
1. Cleared cache, data and updates of Google Play, Google Service Framework, Google Play Service, Download manager
2. Removing and re-adding my account
3. Using different Google IDs to download
4. Using apps like Obb2SD, Obb on SD, link2SD etc to try move the heavy obb files from emulated storage to the actual external SD in order to free up space
But none of them have worked so far. So I'm stuck with 490MB of free space on my device and yet I cannot update even a 2MB app. The problem is not with my Google ID or Network as I used them to download apps on my phone as well and they installed even when space is running as low as only 100MB. Can anyone suggest a solution for this? How can I get rid of this error/move apps to External SD and free up space? Thanks.