Windows Phone 7 apparently sees any microSD cards inserted into the smartphone as a "permanent modification," rewriting the removable memory in ways that make it useless to any other type of device. One of the inaugural Windows Phone 7 smartphones, the Samsung Focus on AT&T, includes a microSD slot for expandable memory.
A subset of Samsung Focus owners are reporting issues with the smartphone's microSD slot, including some cards' inability to function with their device. According to AT&T, Windows Phone 7 requires a certified high-speed microSD card for "optimal performance."
Microsoft previously offered a support document about Windows Phone 7's microSD usage. "To help ensure a great user experience, Microsoft has performed exhaustive testing to determine which SD cards perform well with Windows Phone 7 devices," that document mentions near the beginning. "Microsoft has worked closely with OEMs and MOs to ensure that they only add these cards to Windows Phone 7 devices." It neglects to mention which types of SD cards "perform well," or the relevant specs.
Indeed, users wanting to know which microSD cards are Windows Phone 7-certified will be disappointed. "This information is not currently marked on any microSD packaging in the market today," AT&T warned in a widely circulated statement. "We are advising customers to delay purchasing an external microSD card until the cards identified as 'Certified for Windows Phone 7' are available commercially or in AT&T stores."
Meanwhile, Microsoft suggested that Windows Phone 7 treats removable memory as nonremovable.
"Windows Phone 7 does not support swapping microSD cards in and out," a Microsoft spokesperson wrote in a Nov. 15 e-mail to eWEEK. "SD cards inserted into a Windows Phone 7 device are integrated into the device's file system and are intended to be a permanent modification to the device."
Once a Windows Phone 7 device integrates the microSD card into its file system, the spokesperson added, "it will no longer be readable or writable on any other device." In addition, "This behavior is by design and is intended to ensure a consistently high-quality and secure end-user experience."
Microsoft spokespeople had initially directed queries about the microSD cards to AT&T. The carrier's representatives, however, referred eWEEK back to Microsoft, which then provided the statement.
Microsoft hopes that Windows Phone 7, which launched in the U.S. market Nov. 8, will allow it to regain lost ground in the smartphone market against competitors such as the Apple iPhone and Google Android. Unlike those smartphones, which employ gridlike screens of individual apps, Windows Phone 7 aggregates Web content and applications into six subject-specific "Hubs," such as "Games" and "Office." On Nov. 15, LG Electronics and AT&T launched the LG Quantum, the fourth device in the Windows Phone 7 line.