When a number sends you a text, how do you add them as a contact instantly?

[quick99si]

Outlook is the native SMS application. If you're in threaded mode and wanted to save a number to your contacts, you would open that thread and simply tap the number near the top of the window where it says "Conversation with (123) 456-789". You should get an option to "Save to People" among others.

Or you can copy/paste it to your contacts manually.

And I would remove the last paragraph from your post if I were you..