is it normal that if i download a free iphone app, the app store ask or verify my credit card number?

[Beloy]

i started downloading instagram which is a free app but they still ask for my credit card. is this normal?

[cybertronz]

No, if it's a free app you are trying to download from Apple's official app store, it only asks for a verification password and nothing else. You should make sure of your download source and don't input personal information such as your credit card number if you are not entirely sure.