If you have the previous version installed, deinstall it and then try again. If not, you might need more space (double to three times the size of the .apk) for the installation precess to finish.
it shouldn't. 8gb isn't much, not sure how much temp space android needs to unpack stuff, so maybe you need more. I'm just guessing here, 'cause most of the time when someone wasn't able to install, the problem was low storage.
