Nintendo 3ds?

With the Nitendo you can go on YouTube so on the Internet. Can you load any app on it so that you can write with someone else who has a cell phone?

No, unfortunately that is not possible.

The only way is that you can write someone a letter on your Nintendo via doodle mail.

A few years ago there was also Miiverse, but unfortunately that was abolished. Unfortunately, I don't know the reason. Probably just too many pedos

So there's also a browser on the 3DS (Internet), you may be able to log in manually on platforms via the Internet (Discord…), but do not know 100% whether it works. WhatsApp e.g. As an application does not exist.

Thank you