White paper | Xperia™ SP LTE
18
January 2014
4.
SD Card
(known as “/ext_card” from a programmer’s point of view, or by other names in other Android
products) is the name for the removable SD memory card in all 2013 Sony Mobile products. As
described above, this External Card memory is generally more limited in that any application can READ
from it, but many applications cannot SAVE to this card. Only a few applications, including back-up
applications and file manger applications, has the capability to save to this card.
Backing up data to different memory types
Generally, you should not save photos, videos and other personal content solely on the internal memory
of a phone. If something should happen with the hardware, or if the phone is lost or stolen, the data stored
on the phone’s internal memory is gone forever.
In a phone where an SD card reader is the main memory, it is relatively easy to take the card out and copy
all content to a PC or Mac, or to an entertainment device with a memory card slot. In a product featuring
Internal Storage as the main memory, it is not possible to physically remove the memory. Instead, any
critical or high-value content must either be copied to an external SD card by a special backup
application, transferred to remote storage over a network (mobile or Wi-Fi), or to a computer via a USB
cable.
To facilitate the transfer of data via a cable, the Xperia™ SP supports the Microsoft standard, Media
Transfer Protocol (MTP), which makes it possible to easily transfer content back and forth between your
phone and a Windows PC. For Apple Mac computers, a special application, BridgeforMac, is available
offering built-in support for MTP; this application can be downloaded from the Xperia™ SP Support page.
Note that you do not need to back up or make a copy of applications that you have downloaded from
Google Play™. They can normally be downloaded again if, once you have set up your Google account to
work in a new phone phone (or a phone where the memory has been completely erased).
Note 1:
As noted above, some Android phones, including Sony Mobile devices from 2012, and Sony Ericsson
devices from 2011 and earlier, do not use a single “Internal Storage” for both applications (and their data)
and user content. Instead, these devices use either an external SD card for user content, or a
corresponding area of internal memory to reproduce the functionality of an SD card. In such devices, there
is a fixed limit between the application area (“/data”) and the user content area (“/sdcard); with the result
that user content can be filled, stopping the taking of new pictures for example, while there is still
considerable free space in the application area; or vice versa, stopping the download and installation of
new applications even though there is free memory in the content area.
Note 2:
Some devices with an integrated storage have abandoned the distinction between the application area
and the content area when it comes to Factory Data Reset. As a result, there is no choice to do Factory
Data Reset and preserve content; in such devices, all content is mandatorily and completely deleted from
the device when a reset is performed.
In contrast, Sony Mobile has done the integration in a manner which makes it possible to preserve user
content in this situation; therefore, when performing a Factory Data Reset, the default will still be to only
remove applications and their data, and an option box must be checked if also all content is to be
removed (as might be desirable when selling the device second-hand, for instance).
Note 3:
For a developer, it is important to note that from a programmer’s point of view, the location names used to
refer to the different memory areas described in Note 1 are still valid; i.e., the area used for application (/
data) is still present, as is the area used for content (/sdcard).