Sometimes the simplest ideas work best.

User Rating: 9 | Pushmo 3DS
Sometimes the simplest ideas work best, which is the case in Pullblox, the best puzzle game on e-shop. The aim of each level is to reach the flag by pulling out the colourful, differently-shaped blocks to be able to get your cute sumo wrestler guy Mallo to the goal. He can walk, jump, and pull blocks, that's it. I know it sounds weird and unappealing (especially when explained by me), but actually it's a fresh, innovative and addictive game. The levels get exceedingly difficult and leaves you wondering how the hell you do it. If you're stuck for long enough, it allows you to skip to the next level, but I think a super guide would have been better. Halfway through the game, pullout switches are adde. These, if stepped on by Mallo, trigger every block that is the same colour as the switch to come out all the way. There are also manholes, which Mallo climbs down to appear in a different place on the level. These thoughtful additions make Pullblox more complicated, but not too complex as to ruin the core idea. The levels are often surprisingly tiny yet could still tax for an hour or more. If done right of course, you could complete them in half a minute. Which brings up another thing: there are no enemies at all- just you, and the blocks. For an e-shop download, Pullblox holds you for ages and ages, with tonnes of levels, many being murals that look like objects, and famous 8-bit Nintendo characters.
You can also design your own levels. This is a massive replay opportunity that makes Pullblox yet better. You can then turn the level into a QR code and another 3DS can then hover over it and download it. I would've preferred an online sharing system instead though, like in Mario and Donkey Kong.
Pullblox is the first game you should download from the e-shop.