To quickly enter a capital letter when typing with one finger, tap and hold the Shift button and slide over to the letter you want to enter.
This capitalizes only that letter and you can carry on typing as normal. This is useful for typing place names like New York or London.
To quickly enter punctuation or numbers from the keyboard, tap and hold the secondary keyboard button and slide to any number or punctuation button.
When the finger is released, that character will be inserted and the usual keyboard reappears.