Managing the emails from LinkedIn:
If you find any particular email from LinkedIn annoying you can click on Unsubscribe link found in the end of that email. You can manage the types and frequency of the email you receive on your iOS app by:
Opening the LinkedIn app.
Then tap the profile picture.
Find the Settings icon on the top right corner of the screen and tap on it.
Then find Communications tab and tap on it.
You would have a list, from that select Emails.
You can turn off email notifications by moving the toggle switch to Off.
The other option is to select Details which is found next to any email category listed. You can choose to either stop receiving email notifications or see other email setting options.