In my personal opinion? If you can type that message out on something, buy terraria on that. It'll always be a much better experience than the 3ds version. Unless you like, want to play the legacy mobile edition. Which is valid since it actually has a few things that desktop and modern mobile don't have. Like more seasonal events, and ocram.
Edit: just realized i misinterpreted what you meant, since you seem to already own the game. 2ds is still a good purchase in the modern era, with a the entire library of ds and 3ds games able to played on it. including some damn good remakes like ocarina of time 3d and (controversially) majora's mask 3d. and a couple mario and luigi remakes. not to mention all of the original games like planet robobot, ever oasis, samus returns (which is a remake but imo changes so much it's barely recognizable compared to the original), and pokemon sun/moon and pokemon x/y.