Weird Data / Wifi Question

Hey fellow crackberries, I've searched all over the thread, but I'm not sure if this has been asked or answered.

My problem is with wifi and data. When I am at home or in school, I use my wifi in the hopes of not racking up my data charges. I also check the service status just to make sure and it does say "Blackberry Internet Service, Connection: wifi." So I should be good right? So I thought. Im still getting random data charges when i check my usage online. Also, I have data services on because if not, I can't use wifi (it will be just greyed out)

Any insights to this? I really want to start using wifi and not getting charged for data.

Hm.. That's interesting. I have an unlimited data plan so it doesn't really matter to me, I still always use Wifi when I can. I can't think of any reason it would do that.. Unless some apps you have can't connect using Wifi so they use your data plan to connect.

i agree with mcstoner to check your apps to see if there is any that runs only using your data plan.

when i travel and i want to avoid the roaming fee for data usage, what i do is go to the mobile options>network>connection preference: wi-fi preferred
and i look through all my apps and set connection method to wi-fi. Hadn't had any problems. If you want to be extra sure about only running on wi-fi and don't care about phone call service, you can just turn the network off and leave wi-fi on.

thanks for your insights guys. now it makes total sense. i will try that, and do some tweaking with some of my apps.

im assuming the facebook app cannot run on wifi right?