Basically, this is everything that the PC version had, except that now you are able to use a stylus, making it easier to do orders, not having to drag the mouse here and there.
Again, you are Jill, who comes back from culinary school, only to discover her grand-parents have almost lost their shop due to a new 'Mega-Mart' store opening.
Each month (a level), you have to serve customers, baking and decorating cakes to earn money for her grand-parent's bakery to open again. You may even make two-layered cakes! The quicker you serve customers, the happier they are, and the more likely they may give you tips.
But make sure not to make too many wrong cakes! As this will take away the price of the cakes lost from what you have earnt in that level. I suggest buying a display case so if you make a wrong cake accidentally, you could put it there, so it doesn't have to go in the bin. Some of the customers do actually buy them, after seeing them on display.
At the end of a level (a month), you may use the money to buy upgrades for the bakery, making it easier for you to serve orders as the levels harden. Such upgrades include more high-tech ovens and icing machines, a display case to display cakes you may have made accidentally, a machine to put little figurines onto the cake, a muffin oven to up the customer's happiness (displayed with hearts), a T.V. that you can change the channels of depending on the type of customer, and even special shoes to make you move faster.
The game lasts for a few years (months/levels in the game), but I, myself, have not completed it yet. Customers are characters like Santa Claus, the Easter Bunny, the local builders, child visitors from the circus where the bakery is (when you move there) and students on holiday. The more you progress in the game, the more money you make, allowing you to improve your bakery, and also to move locations. The more you play, the harder it also gets. But the touch screen allows you to complete orders quicker than the PC version, where I had to drag the mouse everywhere. Now you can use the stylus to hand out menus, collect cash, serve muffins and everything else.
Overall, you will have to decide which game to get, depending on whether you favour the big screen on the PC version, or the touch screen on the DS.