iOS 7 has changed the keyboard you can use when typing on your iPhone, iPad or iPod touch. One of the changes is the removal of the .com button; the button that let you type “.com” with a single keypress when entering web addresses.
While this button won’t be coming back soon, there’s a way to type .com with one-and-a-half keypresses. When you’re in a web browser, and want to type .com, just tap and hold the . button to the right of the space bar, and you’ll see a popup menu which lets you choose from a number of top-level domains: as you can see below, I can choose from .us, .org, .edu, .net and .com.
If your region settings are not set to United States, you’ll have some different options: for example, if you’re in the United Kingdom, you’ll see .co.uk; if you’re in France, you’ll see .fr; and so on.
(By the way, this isn’t new; it’s been part of iOS for a long time. But since the .com button has disappeared, many people who didn’t know about this tip will benefit.)
There are other typing shortcuts you can use with this same technique. See iOS 7 Quick Typing Tips: Quickly Type Capital Letters and Punctuation
Also, iOS 7 keyboards are contextual; they change according to which app you use. See this article for more.