Droid 4 SD Card Issues: Data corruption errors. What SD card to use with ur Droid 4?

[tutorialbs]

My brand new 32GB SanDisk SD card had a very high rate of data corruption in my Droid 4. The card worked perfectly, until I use it in my Droid 4.
So...The reasons I think this is a compatibility issue are:

1. I tested the 32GB SanDisk SD card extensively (20+ hours) separately, in an SD card USB converter, and with multiple check-disk programs. 0 errors, clean surface.
2. Before the SanDisk, I used a 4GB Kingston SD card, also Class 4, which never had any corruption issues.
3. I searched Google, and other Droid 4 owners are reporting similar SD card data corruption problems.

Problem:
I bought a Sandisk 32GB MicroSDHC/SD Card, Class 4, and started getting errors as soon as I put it in my Droid 4. I would transfer apps via my USB cable, and the files would look OK in the phone's file manager, but when I tried to open or run them, they would do 1 of 4 things at random: Error, just disappear, go from their normal size to 0kb & not open, or work for a few seconds but then error/close.

[tutorialbs]

Am revising my original post now that I've got a better idea of what happened.

The SD cards I bought were cheaply made SanDisk 32GB (Class 4) cards, though they did come in retail packaging. All 3 cards I bought have similar "bad" areas with inconsistent quality that results in inconsistent Read/Write speeds. About 95% of the cards run at Class 6 speeds, while about 5% run at Class 2 speeds. Fortunately, these slow areas were all concentrated at the very start of the disk storage area, which I determined by running many hard drive surface scans. I completely erased each disk and then repartitioned all the cards to not use the first 300MB-400MB of disk space, so I've about 28.7GB total instead of 29.1GB total. After doing that, I haven't had a single error having to do with data corruption or anything else, and the all the cards now run at Class 6 or slightly higher speeds (even though they had various slow areas in the middle of the disks, those seem to have been eliminated by eliminating the use of the largest concentration of slow disk area).

I'm scanning my other external drives to use this technique, too. It's interesting (and rather obvious, when it's a pattern and not damage) to see which brands skimp on disk quality.

One thing I'm still unsure of is why my Droid 4 was incompatible with the cards, at one point, while my computer was not. I think it's either that my phone is picky about the type of class the SD card must be, or all Droid 4s are like that. My SD cards originally ran at Class 2-6, the variation in speeds at the front of the disks and in many other places before repartitioning, may have caused instability and data corruption.

[640k]

so what I see missing from your run-down is the methods used. did you ever try formatting your cards while in the device? use android's built-in formatting option?

fwiw, I have been using the same 16GB SD card that came with my D1 since 2010. I use it less extensively these days than I used to, but it has traveled with me in every DROID device I've owned.