That is exactly my grandchildren. My grandson is four and has been using smartphones for three years. He's had his own for one. Color me shocked when, at three, he asked me to connect his phone to my wifi. They're bright enough kids but far from exceptional/genius. Its just how it is now.

By the way, when you make the off/end button big and red, it is nigh impossible to convince a little boy not to press it. Over and over.