I've had my S4 for over a week now, however I haven't put in an SD card yet. I was thinking of getting a 32GB one. What cards would you guys recommend? Also by putting music and or videos on an SD card does that still allow me to play them through the apps on my phone? (such as the music player)
This is the one I have:
Amazon.com: SanDisk Ultra 32 GB MicroSDHC C10/UHS1 Memory Card with Adapter (SDSDQU-032G-AFFP-A): Electronics
Different folks will give you different opinions based on their experiences (Samsung has their own brand of SD cards that seem to work better for some folks), but I've never had an issue with SanDisk cards. I'd definitely recommend staying away from cheap generic cards though.
When the card is new, put it in the phone and format it (Settings --> More --> Storage --> Format SD Card), then plug your phone into your computer with the USB cable. You should see 2 directories now for your phone, the internal storage and the card storage. Simply copy any files you want to the SD card directory and you're good to go. Oh, and yes, any media you place on the card (music, video, pics) will be accessible to the apps on your phone.
EDIT: One other piece of advice: MicroSD cards are extremely convenient, but not always the most reliable form of storage. I've had SD cards that lasted for years with no issues at all, and others that crapped out after a few months. NEVER keep your
ONLY copy of anything important on it. I generally try to back mine up to my computer every few months just to be safe.