The Japanese Nintendo Switch will be launched on the 3rd of March. The Switch is considered by the company as a "hybrid" console. Designed as a home console, with the main console unit inserted onto a docking station to connect to a TV, the console can be removed and work as a personal tablet computer (LCD + Touchscreen) or also placed in a tabletop mode to play with several people.
If you've preordered or not, these are the main info you have to keep in mind:
#1 USB-C Cables
The device comes with an USB-C charger, directly connected to the console.
It is suggested that you get extra USB-C cables if you want to charge your device away on from your TV. We would suggest you buy USB-C to USB-C cables.
#2 MICROSD Cards
You can normally use microSD cards up to 2TB. These cards aren't created equal and their specs have more than storage capacity.
It is suggested that you use the one you already have. The Nintendo Switch is compatible with SDXC cards, compatible with the older capacity SD and SDHC cards.
Otherwise, you can also buy a new one: Nintendo Switch-branded cards, the Hori card.
#3 CASE
One of the most interesting things about this device is that you take it with you everywhere.
So, you will probably need a case. After all the options already up for preorder online, the PDP's $15 looks like it will do the job.
#4 ETHERNET Adapter
If you want to play online (through Ethernet), you will need a USB adapter to use with the Switch dock. Nintendo launched its own one for $30 but you can also go for cheaper options.
Source (c): Nintendo Website, The Verge