I've been holding out upgrading to S4 until I can get a 32GB or 64GB. It's my understanding (from what I read here) that I will no longer be able to move apps from internal memory to the SD card. And since Sprint has no idea how long it will be before these phones are available, I wonder about the apps I see in Google Play that can move apps to the SD card. Have any of you used them with your GS4? What was your experience? Thanks!