Swapnote is a messaging service for the Nintendo 3DS where you can send notes to other users via StreetPass or SpotPass. The app is completely free to use unlike its sequel, Swapdoodle. Some features, like sending images, are unlocked for free by creating enough notes while others (like voice memos, which require Play Coins to unlock) are not.
Writing a note
Notes have many options for how to write one. When you write a note on the bottom screen it will also appear on the top screen as a clearer image. You can draw up to 4 pages in one note. The scribe can add photos saved on the 3DS camera to their note. If the image is big enough it will be automatically cropped.
Drawing and erasing
The scribe is given a Pen, 3D Pen, Eraser and a 3D eraser. Both pens can write in multiple colors including Black, Red, Blue, Yellow, Green, and Purple. The normal eraser can get rid of non 3D doodles, while the 3D eraser does the opposite.
The scribe has the option to send a 5 second voice message. If a voice message is longer then 5 seconds it will be cropped. This feature requires 10 Play Coins to use.
Stationeries are backgrounds for a note that you can buy with Play Coins or receive special stationery via StreetPass with someone who owns one. There are 6 unlocked by default: plain, musical, a plate, a sun where the center is your personal Mii, a postcard with your personal Mii, and a house on a hill. After you send enough notes, more default stationaries will unlock like an outer space one and a news report one, costing 5 Play Coins each.
Time stamps are a feature that let you set a note's creation date back or forward. If you set a note to the future, the note will be locked until that day arrives. This only works with noted that have been sent.
The inkwell is a border to how much you can draw. it is located in between the pen and eraser. The more you draw the less ink the inkwell has. The max capacity in the inkwell cannot be changed, unlike swapdoodle. The 2D and 3D pen both share the same inkwell.
The max note limit is 4000. Atfer 100 notes, Nikki will send you a note, telling you about reaching 100 notes and the 4000 note limit.
The SpotPass feature of the app was discontinued on October 31st, 2013 due to offensive imagery being sent through the service. However, the StreetPass function still works, meaning you can still send and receive notes locally.