Setting up Unity to Export Android apk

OK so today I spent hours trying to figure out why my unity 3D project wouldn’t build. I found several different solutions for anyone who might have these same problems in the future.

1. Make sure that your android SDK version is 21 or older. For some reason any updates above 21 cause problems with unity. If you need to revert to 21, you can download it by clicking the following link:
2. Make sure that you copy the abd.exe file from the platform tools folder and put it in the tools folder. Here is a great tutorial video that explain the process perfectly.
3. Install JDK 32 bit

Here are some great resources.