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Sprint Product Ambassadors: What is Adoptable Storage?

Sprint Product Ambassador


Anyone who follows Android closely may have become aware of some debate in the Android community around the new way that Google has engineered memory implementation in Android 6.0.  We here at the Product Ambassador team have an gnawing curiosity about these kinds of things and wanted to explore this a little further.

Android has long been criticized by lack of adequate support for removable storage such as SD cards. evidenced by lack of SD card slots on Nexus devices, a trend which continues in the latest devices, Nexus 5x and Nexus 6p.

In pre KitKat 4.0 devices, SD card support in Android did not have clear guidelines for app developers and was poorly implemented with a basic lack of standards for application developers and OEMs to adhere to but still basically worked as an external removable memory partition on a device. 

In KitKat 4.0, SD card support was radically restricted to only allow SD cards access to application specific directories due to "security reasons" (at least according to Google) which broke applications and even changed functionality in things like the camera.

In Lollipop 5.0, the application specific directory requirement was relaxed to allow apps access to non app specific directories which improved the user experience but still kept the memory separate from internal storage which prevented certain apps from saving data to SD cards properly.  This caused more ROM to be used on the device vs the card resulting in user complaints especially for very large files such as media and game data.

In Android 6.0, Google has fixed many of the issues. Marshmallow introduces the concept of Adoptable Storage and Portable Storage. Adoptable Storage enables a user to set up their SD card as a true internal memory partition and store application data on an "adopted" SD card.

With Android 6.0, many OEMs are now deprecating any existing 'move apps to SD' feature they may have built in their Android builds or "skins" which enabled the user to move applications to a SD card in favor of the richer experience natively provided by Android.

While Adoptable Storage is an improvement in how Android allocates memory for SD cards, it is not perfect.  There are card speed requirements above Class 6, preferably UHS-1 and there is also a requirement to encrypt the card which will result in reformatting once the card is removed from the device.  The intent is to essentially keep the card in the device indefinitely which is not very acceptable to people who want to use the card in other devices and media. 

"Adoptable"/Internal Storage

  • A user should select this mode if they want to completely extend their device storage with the card, and need the card to store large applications, games, and their data.
  • They have a high-speed card (preferably UHS-1).
  • If the user wants to store large games or other app data on the card, if their device storage is always filling up its RAM, and they plan to always keep this card in the device, the recommendation is to keep the card as internal.

Portable Storage:

  • A user should select this mode if they frequently swap their SD card between devices and use their SD card for media storage only.
  • They have a Class 2, 4, or 6 card.
  • If they frequently swap cards, use their SD card to transfer content between devices and do not download many large apps, the recommendation is to configuring their card as "portable".
  • Only pictures and media can be stored on the card. Downloaded applications and their data, is always internal and cannot be moved to the card.
  • The card is readable by other devices. (another phone, Mac, PC, digital camera)
  • Content on the card is not encrypted by default.
  • The card will NOT be reformatted when Portable storage is selected.

So, the Samsung Galaxy S7 supports Adoptable Storage right?


But why not?

Samsung believes that formatting the SD card to act as internal memory results in a poor user experience and created the following statement to explain more around why they made this decision:

"Samsung decided not to use the Android Marshmallow 'adoptable storage' model. We believe that our users want a microSD card to transfer files between their phone and other devices (laptop, tablet, etc.), especially the photos and videos they shoot with the camera.

With adoptable storage, first of all the card may be erased the first time it is inserted into the device. This behavior may be unexpected by many users and we don't want our users to lose their files. Second, once Marshmallow starts using a card for adoptable storage, it cannot be read by other devices, so it loses this ability to be used for file transfer. Adoptable Storage is also primarily targeted towards emerging markets where devices with only 4 (GB) to 8 GB of onboard storage are common. We think that our model of using microSD for mass storage is more in-line with our owner's (sic) desires and expectations for how microSD should behave."

That said, there is some limited ability to move apps to SD via application manager>find app>storage but it's very hit and miss and app dependent so I'm not sure how useful it will be to the average user.

We'll have to wait and see if Samsung changes their tune down the line around Adoptable Storage vs Portable Storage or if eventually Google will cave to the pressure from OEMs like Samsung who do not allow it and make changes necessary to make everyone happy.

Until next time,

The Product Ambassador Team

Disclaimer: The Product Ambassadors are Sprint employees from many different parts of the company that love technology. They volunteer to test out all sorts of Sprint devices and offer opinions freely to the Community. Each Product Ambassador shares their own opinions of these devices, therefore the information in this post does not necessarily reflect the opinions of Sprint. The PA's do not represent the company in an official way, and should not be expected to respond to Community members in an official capacity. #sprintemployee#