Like the topic title says, does having fewer email accounts have any difference on the speed of one's blackberry?
I cannot think of a single reason why it would make a difference in normal use of your smartphone. It was designed to handle 10 email accounts plus one hosted account and I think a huge amount of BlackBerry owners max these out.
Maybe you can give us more details if you notice your device is running slow. I am sure somebody here can offer suggestions. There are quite a few informed BlackBerry owners in these forums.
If it's running slow, close out more than one of those apps. Press and hold Menu, select the app, exit it, repeat until the 5 remaining are shown, which never close.
Posted from my CrackBerry at wapforums.crackberry.com
