This will show you how to quickly insert punctuation on iphone and ipad.

instead of pressing the ‘123’ key then inserting punctuation, then pressing the ‘ABC’ key to get back simply hold down on the 123 key and, without letting go you will notice that the keyboard changes.

you can simply hold down the 123 key and then move to the key you want without letting go, it will insert that key and then, when you let go, it will return to the ABC keyboard!