Popped it in to my BLU R1 HD (16GB Storage, 2GB RAM, with Amazon AD), and it automatically detected that it was Samsung EVO and gave me options to use. I chose portable media storage, and I was able to quickly transfer my music files to the card (it was really fast!), and there were no problems playing the music from it. After using it for a week, the phone accessing the files (music and pictures) was snappy. Whether the phone was rebooted, power off/on, the SD card had no glitches.NOTE: For smartphones, Class 10 micro SD card is a necessity for speed. If anything less than Class 10, the speed suffers and apps often stutter or lag (I tried my Class 4 micro SD card on the phone, and it was slow). So if you own a smartphone and use micro SD card, check whether you are using Class 4 or Class 10 (or above). You will see the difference in speed. With Samsung EVO (Class 10), you are good to go!All in all, I am very happy with the product (given the price point - $6.99). Highly recommended!