The one linked in Jefftheworld's Best apps
is a root app, so you have to root your vox, but it is called 'ShootMe' I assume this is the one JefftheWorld uses as he links it as one of his best ones..
I did find this one that is non-root: http://www.apktops.com/no-root-screenshot-it-2-10.html
I'm not sure how well it is as I have a rooted device and have installed the ShootMe app instead. Reading further it has to go through a computer, so it may not be best.