Gmail has become one of the best email services and it is famous across the world for its excellent features. To add existing Gmail accounts to your iPhone, you will need to open the Gmail app on your iPad or iPhone. Now, tap on your profile picture that appears in the top-right. Tap on the Add another account and then, select the type of account which you want to add. Now, follow the steps on the screen to add your account and call on Gmail Helpline Service Number UK to get in touch with the technical experts for any assistance.