HTC One delete your Google & Gmail account

OS: Android 4.1.2 (Jelly Bean), upgradable to 5 (Lollipop); Sense UI 5

CPU: Quad-core 1.7 GHz Krait 300

Display: 4.7" inc

Camera: 4 MP, Single

Remove a Google account on HTC One

You need to be sure to remove your Google account from your phone if you transfer the phone to another user and do not want him to get access to your mail or other Google services.

What happens after deleting a Google account?
All data and content will be deleted, including emails, files, and photos.
The phone user will not be able to access Google services that require an account (such as Gmail, Drive, Google Play or Calendar).
You will lose access to subscriptions and content purchased through this account on Google Play and YouTube (for example, applications, games, music, TV series).

How do I remove a Google account from my phone?
Open the Settings app on your phone.
Now, select the Accounts and backup menu item.
Select Manage accounts to get a list of accounts on your device.