brendannee

Keep your site’s content fresh. This plugin adds a box to the WordPress admin dashboard that lists all pages that haven’t been updated in recently. Every time you log in you’ll be able to quickly see which pages might need review to ensure the content is still correct and everything is up to date.
You can set the threshold in days for considering a page “old”, the default is 90 days.

Old Page Reminder

This plugin adds a box to the Wordpress admin dashboard that lists all pages that haven't been updated in 90 days.

Lucas Garcia

Posts reminder notifies you when you forget to write a post on the current day. It notifies you at 22:00 to the email you specifiy on the options page.

Posts reminder

Posts reminder notifies you when you forget to write a post on the current day.

Old Page Reminder vs Posts reminder