The suitable memory card for the Sansui 181 will be a 4 or 8 GB microSD card as the phone has an expandable memory capacity of 16 GB. The phone comes with 32 MB of RAM and for this less value, using small capacity card would be a better option as accessing larger data would interrupt the smooth functioning of the phone. The size of files being used on the memory card should be kept as small as possible as processing bigger files would not be possible. The phone comes in a bar factor with very less features on board.