Yes, you can delete your email account on your iPhone and lose all of your contacts. However, if you have any important emails that you want to keep, you may want to save them to a computer or another email account so that you can access them later.
You’ll lose contacts that are solely in your Google Account instead of being separated on your device.
If your exchange contacts are shown on iCloud.com, you should be able to access Settings Mail, Contacts, Calendars then tap your exchange account and choose Delete or Sync Contacts. The exchange contacts will be removed from your phone but not from iCloud.
All Email Accounts Are Entailed. Even if you delete an email account from your iPhone, the account and address remain intact on the phone. You may still receive and send emails using the web or other email systems that have been configured to utilize the email account.
Deletion of a Gmail account is permanent. All of your emails and account settings will be removed after you complete the procedure. You will no longer be able to use your Gmail address to send or receive emails, and it will not be made available for anyone else to use in the future.
You can also delete an app from your device by going to the Settings menu, selecting “General,” then “Application Management,” choosing the affected application, and tapping. Delete.
