Even though the official R4DS site (www.r4ds.com) says it supports 4GB TF MicroSD cards, I have yet to find one that is not SDHC. They seem to be very elusive or does not exist. I would just get the 2GB microSD to be safe.
Here's a clip from the R4DS FAQ:
Q: How many files can I have on the R4?
A: R4 Adapter supports 128MB~4GB TF(MicroSD) card , 4GB=32Gbit
re: Type of 4GB MicroSD
Even though the official R4DS site (www.r4ds.com) says it supports 4GB TF MicroSD cards, I have yet to find one that is not SDHC. They seem to be very elusive or does not exist. I would just get the 2GB microSD to be safe.
Here's a clip from the R4DS FAQ:
Q: How many files can I have on the R4?
A: R4 Adapter supports 128MB~4GB TF(MicroSD) card , 4GB=32Gbit