Sd Card In Samsung Galaxy 6

[Captain Spod]

So many nice Apps out there but my new Samsung Galaxy 6 phone says I haven't got enough memory. I have fitted a 4gb SD card and formatted in within the phone. The phone knows it's there as it reports available memory in the storage settings page but it won't direct anything to it. How do I persuade it?
TIA

[Buenchico]

http://www.samsung.com/uk/support/skp/faq/1030441