when the application memory gets low, the phone can't run as well as it should. It's telling you that because you are at 0, meaning things like your e-mails, texts and calendar entries will start to be automatically deleted for space.
1. GET RID of the theme, number 1 hog of any space you have.
2. WeatherBug, Viigo and Poynt have all also be known to be memory hogs.
If you use them that's fine but your phone is trying to tell you to remove things for a reason.
thank you very much for your advice. i always saw my memory through BB App World so i wasn't sure why this new pop up screen was coming up. i'll delete some apps, thanks again!!