Like all flash memory devices, flash drives can sustain only a limited number of write and erase cycles before the drive fails.[71][unreliable source?][72] This should be a consideration when using a flash drive to run application software or an operating system. To address this, as well as space limitations, some developers have produced special versions of operating systems (such as Linux in Live USB)[73] or commonplace applications (such as Mozilla Firefox) designed to run from flash drives. These are typically optimized for size and configured to place temporary or intermediate files in the computer's main RAM rather than store them temporarily on the flash drive.
A minority of flash drives support biometric fingerprinting to confirm the user's identity. As of mid-2005,[needs update] this was an expensive alternative to standard password protection offered on many new USB flash storage devices. Most fingerprint scanning drives rely upon the host operating system to validate the fingerprint via a software driver, often restricting the drive to Microsoft Windows computers. However, there are USB drives with fingerprint scanners which use controllers that allow access to protected data without any authentication.[70]
Our tester highly recommended this flash drive for iOS mobile users: “The iXpand is a great resource for backing up media files and for expanding storage, as well as transferring files to a PC.” He added, “The Drive App is easy to navigate and copy files with, as well as operate the camera and play music and video files.” On the other hand, our reviewer reported, “The 30 MB/s write speed on PC is far from horrible but definitely slow for the asking price, and we calculated only about a 12 MB/s when connected to an iOS device.” He ultimately concluded, “A slightly cheaper price would make it the surefire winner in the Lightning connector category.”
Most USB flash drives weigh less than 30 g (1 oz).[31] While some manufacturers are competing for the smallest size[32] with the biggest memory,[33] some manufacturers differentiate their products by using elaborate housings, which are often bulky and make the drive difficult to connect to the USB port. Because the USB port connectors on a computer housing are often closely spaced, plugging a flash drive into a USB port may block an adjacent port. Such devices may carry the USB logo only if sold with a separate extension cable. Such cables are USB-compatible but do not conform to the USB standard.[34][35]

Audio tape cassettes and high-capacity floppy disks (e.g., Imation SuperDisk), and other forms of drives with removable magnetic media, such as the Iomega Zip and Jaz drives, are now largely obsolete and rarely used. There are products in today's market that will emulate these legacy drives for both tape and disk (SCSI1/SCSI2, SASI, Magneto optic, Ricoh ZIP, Jaz, IBM3590/ Fujitsu 3490E and Bernoulli for example) in state-of-the-art Compact Flash storage devices – CF2SCSI.

Capacity - More so than any other feature, capacity will drive the price of a flash drive up the most. So before you make a purchase, consider how much you’re willing to spend on a flash drive and weigh that against how much capacity you’ll likely need. A flash drive with 16GB can cost you as little as $10, while a 128GB one will run up to $60 or more.

Artists have sold or given away USB flash drives, with the first instance believed to be in 2004 when the German punk band Wizo released the Stick EP, only as a USB drive. In addition to five high-bitrate MP3s, it also included a video, pictures, lyrics, and guitar tablature.[58] Subsequently, artists including Nine Inch Nails and Kylie Minogue[59] have released music and promotional material on USB flash drives. The first USB album to be released in the UK was Kiss Does... Rave, a compilation album released by the Kiss Network in April 2007.[60]

Many people rely exclusively on the cloud for storing their data; it’s convenient and you can get a lot of storage for free. While storing data online certainly has its advantages, it also has serious drawbacks. The most obvious is security. Anything that is kept online is susceptible to security breaches, and news stories about many of the largest corporations suffering hacks only confirms that our online lives are not as safe as we may like.
Flash memory cards, e.g., Secure Digital cards, are available in various formats and capacities, and are used by many consumer devices. However, while virtually all PCs have USB ports, allowing the use of USB flash drives, memory card readers are not commonly supplied as standard equipment (particularly with desktop computers). Although inexpensive card readers are available that read many common formats, this results in two pieces of portable equipment (card plus reader) rather than one.
Most USB-based flash technology integrates a printed circuit board with a metal tip, which is simply soldered on. As a result, the stress point is where the two pieces join. The quality control of some manufacturers does not ensure a proper solder temperature, further weakening the stress point.[77][78] Since many flash drives stick out from computers, they are likely to be bumped repeatedly and may break at the stress point. Most of the time, a break at the stress point tears the joint from the printed circuit board and results in permanent damage. However, some manufacturers produce discreet flash drives that do not stick out, and others use a solid metal uni-body that has no easily discernible stress point. SD cards serve as a good alternative to USB drives since they can be inserted flush.
“The solid state flash drive can theoretically achieve incredibly high transfer speeds, blurring the line between an external solid state drive and a flash drive,” our tester raved. He did note he was “unable to reach higher than half the listed read and write speeds.” However, he explained, “The Extreme Pro is still very fast compared to other USB 3.0 flash drives.” In the end, our tester recommended this flash drive “with the caveat that there's a good chance you won't see those 300+ MB/s transfer speeds.” He also added that for just a little more, you could invest in an external hard drive—if the ultra-compact form factor isn’t important in your buying decision.
There's a lot to choose from when it comes to buying a flash drive. The most important thing to consider is size. The whole point of a USB drive is to store lots of data in a small space, so think about what kinds of files you'll want to house on your flash drive. Movies and music take quite a bit of space, so if you're carrying your whole entertainment library with you, you'll want a big thumb drive – at least 16GB. Books and other text-based documents require relatively little storage space, so people like students and working professionals using Microsoft Office would be happy transferring Word documents or Excel files with as little as 1GB of space. On the other hand, if you are using photo or music editing software, you'll want a USB flash drive with lots of storage capacity to transfer graphic and music files.