Reply to Kontrol S4 + Smartphone

Hey

I am new to DJing and I wanted some guidance.

I have just bought a Native Instruments Kontrol S4. My question is; can I connect my S4 to my Apple iphone 4S or Samsung Galaxy S3?

Also, in case my laptop crashes while playing; what sort of quickie backup options do I have with the S4 so that I can continue playing while the laptop boots etc.? I don't own a CDJ or Vinyl, nor do I have the budget right now.

Thanks