How to check my email in gmail inbox while using iPhone 4 s?

How can I check my email in gmail inbox while using iPhone 4 s?

You need to have added your gmail account to your phone.
Go to Settings>Mail, Contacts, Calendars>Add Account.
Select the gmail logo then enter your email address & password. When you wish to check your email make sure it is turned on & select MAIL icon on your phone.
http://support.apple.com/.../kb/ht4810

Or you can download the gmail app
https://support.google.com/...er/3008051