You can search for text on the current web page using your iPhone or iPad just as you can with a desktop computer. The trick is knowing how to start a search. You start by using the address field, which feels like you are about to leave the page. But if you look at the search suggestions, you'll find a On This Page item at the very bottom that allows you to find the text on the current page instead. You can then use a new search field at the bottom and arrows to find more matches.