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Question: Question about SDHC card class numbers With regards to the SDHC memory cards, does the Class 2 or 4 or 6 or 10 refer to photo taking and video recording only? If I am just buying a card to transfer songs onto it to put into my MP3 player to listen to music, does the class number make a difference in any way? Thank you for your help.
Document: I am happy with my memory card so far. Ive owned it for 2 months now. I do wish it was a class 6 or higher rather than just class 4. But after doing a lot research I found that class 6 or higher only comes in handy for transfer speeds when using an adapter which I never do. I always have my HTC Sensation hooked up via micro usb or wirelesesly for syncing. Also the higher class speed would come in handy when taking 1080p videos which I rarely do.
The card was put in my new Droid Razr on launch day, replacing the stock Micro SD card that came with the phone. Formatted easily. I have since transferred over 20 gb of music files onto it and the transfer speed meets or exceeds 4 mbps for all my transfers. I have also recorded 720p video from my phone and it was stored on this card perfectly. Playback has been perfect.
This is a great card, I was worried that it woudn't work with my windows phone, I heard so much about the cards being incompatible...thank goodness it isn't true with this card...I can no fit a majority of my music on the phone and can use the phone as my MP3 Player...Yeah.
This is a pretty decent card, but it is no speed demon. If you want speed, you will have to get a standard SDHC (if it fits). I got the standard class 10 Sandisk SDHC and it is fast at 6-7MBps transfer rate. This MicroSD is only around 2MBps, which is a bit disappointed.
This is one item that you can bet will be going up in price over the next few months due to supply issues. I upgraded my phone to Android 2.2 which makes better use of the SD card. I read about the different speeds of SDHC and based on my research it is worth buying this brand name SanDisk memory. They actually rate their memory speeds conservatively to make sure performance rocks.
Ordered this card for my MP3 player, but have used it in my digital cameras as well with the adapter. Solid performance for a CLASS 4 card. Much better pricing than the big box stores, and most of them don't even stock any cards over 8 GB. The addition of this card brings to a total of 10 Sandisk cards and thumbdrives and I haven't had a problem with a SanDisk product.
I purchased this micro SD Class 4 for my phone for $33.90. Now you can purchase a class 10 for less than $20. It does it duty. Holds a lot of songs and apps. I can't tell the difference between the write/read speeds since i have yet to get a class 10 and compare but it is great for me.
I bought this for my HTC Surround phone (Windows Phone 7) and it worked wonderfully. The card that I actually received was a Class 4 -- 32GB SDHC card by Samsung, but I'm not complaining. The phone can slow down slightly when syncing music and then playing a game, though, but aside from that, it works well enough for my needs. I can now have 4100 songs on my Win Phone instead of the previous 1700.
They may not perform to exact specs that are defined by the manufacturer, but the difference between how they perform compared to each other is noticeable. In other words, a class 2 card will be slower than a class 4 and a class 6 is faster. That's all you really need to know if you're using this card for the Samsung Focus.
Recieved a 32 GB SanDisk Class 4 MicroSD card, as shown. I didn't run a measured benchmark, but transferring files is noticeably faster than my old Class 2 card (as it should be).One thought though, if you intend to buy for an Android device. My device supports up to Class 6. Feeling confident about Class 4 SanDisk or Class 10 Patriot, I saved about $50 going with the Class 4 SanDisk.
Answer: class refers to the minimum transfer speed, and as far as i could tell from the sandisk web site, their 32gb microsd cards are class 2, regardless of what the picture looks like on amazon.  in theory, when transferring data it might take twice as long as a class 4, thrice as long as a class 6, etc., which might matter if you're impatient and moving gigabytes of data.  it should be more than fast enough for just listening to music.  in my experience, i get higher than the minimum, and class 2 has been good enough for my dslr and recording 640x480 video on my compact camera.