How to use Apple ios 10 invisible ink SMS?

1. The recipient's mobile phone must be upgraded to IOS 10, and the iMessage function must be turned on.

2.① Enter the phone settings-General-Auxiliary Functions-3D touch and turn on the 3D touch switch.

② Select a receiver (the receiver must upgrade to IOS 10 and turn on the imessage function) to send iMessage information. After inputting the information content, press and hold the send arrow, select invisible ink, and click the send arrow.

(3) Send successfully, and the recipient needs to slide on the content to see the text content.

3, send and receive need to connect to the network.