Sony E2363 User Manual

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White paper | Xperia™ M4 Aqua Dual
16
July 2015
Memory in Android™ devices
To use Android devices efficiently, users should be aware of the different types of device memory. This 
knowledge is important in order to understand, for example, where data such as music, photos and 
videos is saved; how many apps can be downloaded from Google Play™; and how photos can be copied 
to a PC.
Information regarding memory presented in this section may be useful to developers when optimising 
applications for mobile devices.
Generally, all Android devices share the same basic memory setup. What differs is how much memory is 
available to you via the different types of memory, and whether your device uses an external SD card or an 
internal memory chip. Any information specific to the particular device model described in this White 
Paper is noted as such.
Types of memory
The types of memory described and numbered below are consistent with the terminology used in Sony 
mobile device menus and in other content relating to 2015 Xperia™ devices:
1.  Dynamic Memory (also known as RAM) is used by applications that run when the device is turned on. 
The amount of Dynamic Memory influences how many applications and operating system services can 
run at the same time. The Android operating system automatically closes applications and services 
that are not being used.
However, such automatic functionality has limits. For example, if a lower amount of free RAM is 
available to applications after a new release of the operating system (due to increased capabilities in 
the system), device speed will eventually be impacted. This is the main reason that a device cannot be 
indefinitely upgraded to newer releases of Android™.
If you experience problems with RAM, for example, if the device runs slower than usual or if the Home 
application restarts frequently when you leave an application, you should minimise the use of apps that 
run all the time. Social networking apps that connect and update their data online and animated 
backgrounds are examples of apps that are always running and affect RAM performance. To minimise 
RAM issues, you could also consider using a static wallpaper instead of a live wallpaper.
To see which apps and services are currently active, go to Settings > Apps > Running. You should 
have at least 50 MB, and ideally 100 MB or more, of free RAM to avoid slowdowns and application 
restarts.
You should also be aware that if you update the device to a later Android release, the load on the built-
in Dynamic Memory will increase due to the addition of more features. As a result, the device may run 
slower after an update.
The Xperia™ M4 Aqua Dual has 2 GB of RAM available to the Android OS and any installed 
applications. 200 MB of the total RAM is in use during normal operation when the user starts using the 
device out of the box.
2.  System Memory (also known as “System partition” or “/system”) is used for the Android OS and for 
most applications that are pre-loaded from the factory. This type of memory is normally locked, and 
can only be changed through a firmware upgrade. There is usually some free space available in this 
section of memory. However, since it is locked, you cannot save apps, photos or any other content to 
this memory. System Memory is reserved for future firmware upgrades, which almost always need 
more memory than the original firmware. You cannot see or influence the use of this memory.