Can't I send a message with a Japanese mobile phone card?

You can send text messages. If you need to open international roaming, you can send text messages normally. Mobile phones, called mobile phones or wireless phones, are usually called mobile phones. At first, they were just a communication tool. In the early days, it was also commonly known as "mobile phone". They are portable telephone terminals that can be widely used. They were originally developed from 1940 battlefield mobile phones manufactured by Bell Laboratories.