Hello again! It is very easy to sideload and install the .apk with just an Android phone and your SHIELD.
Download the .apk to your phones storage
Install AndSMB from the Play Store on your phone
Turn on network file sharing in your SHIELD's settings
Input the credentials into AndSMB similar to this:
On your SHIELD, go to the Play Store and search for 'File Manager', the second one, just called File Manager by HiMedia. It's extremely easy to use and hands down the best file manager for the SHIELD, because of it's simplicity.
VOILA, all done from your phone. And now you have an easy way into your SHIELD from your phone with AndSMB. Extremely useful to have.