Can't sign into Google apps on new iPhone

Something similar has been posted before by 'limari712' but took a lot of finding. As it provided a relatively simple solution to this problem that I, and many others have I, thought it would be worth posting an edited version of the solution below.

I had this problem, too, after getting a new iPhone. You need access to your Google account from another device, computer or laptop and sign in. Then navigate to the "Security" section in your Google account, scroll down to "Your devices," find all the old phones in the list, and click "Sign out" next each one to remove its access to your Google account.  You should then be able to sign into your Google account with your new iPhone. You should get the option to send a verification code sent to a specified phone number (already listed in how you sign in to Google), which then arrives by text message that you can then enter.

Another small point, try to ensure your new iPhone has a different name to the old one. You can change it by going into Settings>About>Name in iOS. This could save some further confusion.