Hello, in this lesson, I will walk you through the NFC Pokemon app flow.

Admin flow#

Let's start from the admin side. On the home screen, the administrator user first presses the CREATE-POKEMON button.

Then the administrator selects the pokemon they want to create from the list.

Our app will jump to the Pokemon Detail Screen, which displays the selected Pokemon info, and the user can press the CREATE button to start the NFC operations.

Let's take a closer look to see the core NFC operations. There're three major steps:

• Password auth

• Write Pokemon data

• Write signature

Let's start with "Password Auth."

This step is used to prevent a third-party application from tampering or overriding the content in our NFC Pokemon tags. This should protect only the write operation. We still need to allow our tags to be read.

The protection mechanism is a proprietary one, which can be found in most of the NXP NTAG product lines.

The second step is, of course, to write the Pokemon data into our NFC tags. We first load the selected Pokemon information, then perform NFC write operation. We will manipulate the NFC tag's internal memory directly, without using a higher-level NDEF operation.

Unlike the previous password protection commands, the commands to read or write the NFC tag's internal memory are not proprietary. They are defined by NFC Forum Type 2 Tag Platform Specification. They are well-known and public and can be used in all Type 2 Tags.