Instability

[tiermann]

If you're not using a task manager, it could be that you just have a lot of un-exited apps running in the background. The "X" button by default only hides an application in windows mobile.

If hard-reseting is your only fix I don't think that's the problem though as a regular soft-reset should fix that. Sounds more like you have very low storage space, maybe due to a large inbox, temp files, PIE cache, ringtones, pictures, anything like that.