Where tiny210v2 GPIO

Where is gpio port on my board?

That's the thing about this board, it does not have any GPIO.

If you need GPIO, you will need to add this by using an extender and
connect via I2C.

You could use the CAMERA port as the connections there can be used as GPIO
but not sure if this is supported in the software. You may need to write a
driver to do this. :)

Do you have a Tiny210V2 module or a full SDK?

On the SDK the SDIO header has lots of useful I/O. I have a few break-out
boards for it. About 1.5x1 inch with a .1 inch hole grid.

The Tiny210V2 core module has 2 unpopulated headers. P4 has the camera
interface, 8 GPIO that are set to interrupt for user switches at boot
(labeled as a 4x4 keypad), IIC, and more.

Otherwise buy an Android pad or phone, an ADK board or IOIO board, connect
them with a USB cable.
But, wait, and then why buy boards from FriendlyARM?
Awesome situation :)