I prefer PayPal whenever possible for on-line purchases simply because it is convenient and limits the number of database in which my credit card information is stored.
how can i do carrier billing.. i actually want to use that to pay for my apps. i have sprint btw
Not sure, sorry. I know initially, there are about 40 carriers (WorldWide) who allow carrier billing. I haven't seen Sprint listed anywhere, but you could always contact Sprint Customer Service and ask.
My carrier (Bell) allows it, and I have that option when I go into Payment Options.
I have to use PayPal, for some reason evrytime I tried to use my bank card it kept getting declined and I got a phone call from my bank about suspicious purchases. And even after I told them it was OK and to approve, it was still declined.