Peter Westwood

This plugin allows your users to configure a reminder to be sent to them if they haven’t posted in the last n days.
You configure the reminder on your Profile page (or the profile of another user if you have than capability)
It is in the Personal Options section and called Blogminder Threshold

PJW Blogminder

This plugin allows your users to configure a reminder to be sent to them if they haven't posted in the last n days.

Imam

Iqamah Times is the first fully-featured application to bring you the iqamah timings of your local masjids with a unique and user-friendly experience. This plugin provides a widget for displaying daily athan and iqamah timings from iqamah.org

Adzan and Iqamah Times – A Simple Reminder

Iqamah Times is the first fully-featured application to bring you the iqamah timings of your local masjids.

PJW Blogminder vs Adzan and Iqamah Times – A Simple Reminder