Can I Jailbreak iPhone4 iOS 6.1.3 and still use the Apple Store?

I'm intrestred in jailbreaking my iPhone with iOS 6.1.3, but am very hesitant because of the fear of loseing apps and messages. If i jailbreak my iphone4 will i be able to download apps from the Apple App Market AND from the Cyndia or whatever the app store is for a jailbroken phone?

Yes. The updates might screw up your phone though.

Yes, I have jailbroken numerous ipods/iphones and everything always works out great