After installing the application, you will notice that an additional FollowUp option had been added in the options menu of your e-mail’s inbox.

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Clicking this option will lead you to the main settings window of the FollowUp application where you can then mark all significant incoming communications and configure the time after which you want to get a reminder so that you can follow up on this communication. I started by marking my important communications and assigning a time after which I wanted to receive a reminder for the marked e-mails. When this time arrived, I was prompted by an alert signaling that I should now respond back to that e-mail. The alert also showed details of the e-mail as I scrolled down the notification message.
I used the latest version of FollowUp that also displayed the task and calendar entries in the notification message and listed the complete detail of the e-mail. This feature allowed me to have an idea about the matter and contents of the message and respond back accordingly without having to revisit the original message. After using the application for a few days, I got used to it and felt that it worked fine for me. The only thing that I disliked about the software was its lack of showing all the marked communications on a single list so that I could quickly and easily view all the follow ups and their subject matter. This application is compatible with almost all BlackBerry models so you don't need to go through a compatibility test for your device.