So, I've been experimenting with ways to enlarge Tanktastic screenshots without much loss in quality. I really can't wait till the update so this becomes easier, but for now this is what I got.
Take this screenshot, for example. I took it by using the friends list:
Now, let's crop out the menu.
Next is the tricky part. it's not 16:9, but cropping it might cut parts of the tanks out.
Luckily it did not, but let's see how enlarging it and sharpening goes...
...And there you go! That's how I make gigantic screenshots of Tanktastic in high quality. Of course, the original screenshot had a bunch of post-processing effects that my laptop's GPU supports. A screenshot from a tablet will have jagged edges on it. There is a way to enable MSAA x4 on Android, though the effect greatly hampers performance.