[General Topics] jdrch:
RULES (READ FIRST):

1) Do not reply with an opinion against the feature, as this thread is not about debating the merits of adoptable storage. Those who like and use the feature don't care that you might think negatively or indifferently about it.

2) Devices and ROMs must support the feature out of the box, i.e. immediately upon device unboxing or ROM installation, without any modifications.

3) Devices - e.g. the Samsung Galaxy S7 - that use hacks such as the Modaco ADB one to enable the feature are NOT considered to support the feature.

4) To add a device or ROM, you must indicate how you know it supports the feature. To do do, you must either:

4a) Personally verify the feature to work on the device or ROM via using it yourself.

4b) Link to official, 1st party documentation/proof that the feature works on the device or ROM.

4c) Link to a forum post or review containing personal verification from 4a)

Each proof will be verified before the device is added. Remember, the idea is that users can reference this thread to help them decide which device to buy. Providing them with poor, incomplete, or inconclusive information before they spend hundreds of USD on a device is unhelpful and irresponsible.

5) When referencing a ROM, include the major version number, e.g. "LineageOS 14.1" or "CyanogenMod 13." It is not necessary to include the minor build number, but it is NOT sufficient to solely reference the ROM name. For example, "LineageOS" by itself is not an acceptable entry.

6) If you'd like to know whether a particular device not listed here supports the feature, please ask! There may be someone who can check for you.

7) Do NOT request adoptable storage support for a device or ROM on this thread. Contact your carrier and device OEM directly, and also request the feature in the forum dedicated to the device or ROM.

8) If a listed ROM or device used to support adoptable storage but no longer does, please post with proof of lack of current support in the form detailed in 4)

If you would like to test a device you don't currently own, simply bring a blank microSD card to you to any retail location the device is displayed at, and ask to test the device for the feature. It's worked for me at Verizon.

Note that a device not supporting adoptable storage out of the box will probably support it if paired with a compatible ROM that does, e.g. while the Samsung Galaxy S5 does not support the feature out of the box, it does support it when LineageOS 14.1 is installed.

For ease of reading, I've tried to put the devices and ROMs in alphabetical order.

ADOPTABLE STORAGE AVAILABLE

Devices

Note: HTC calls adoptable storage "flex storage."

- Asus ZenFone AR - Tested in Verizon store by [MENTION=5909804]jdrch[/MENTION]

- BlackBerry DTEK50 - Pocket-lint review - Thanks [MENTION=7060679]thurask[/MENTION]

- BlackBerry DTEK60 - ZDNet Review - Thanks [MENTION=7060679]thurask[/MENTION]

- BlackBerry KEYone - CrackBerry Forums - Thanks [MENTION=7060679]thurask[/MENTION]

- BlackBerry Priv - CrackBerry Forums - Thanks [MENTION=7060679]thurask[/MENTION]

- HTC 10 - Official specs

- HTC U11 - Official specs

- Motorola G3 - Lenovo Forums

- Motorola Droid Turbo 2 (running Android 6.0+) - Motorola documentation

- Motorola Moto X Pure (running Android 6.0+) - Lenovo Support

- Motorola Z Force Droid - PC Magazine review

- Motorola Z2 Play - Tested in Verizon store by [MENTION=5909804]jdrch[/MENTION]

- Nvidia Shield K1 - Owner confirmed by [MENTION=5909804]jdrch[/MENTION]

ROMs

- CyanogenMod 13 - User confirmed by [MENTION=5909804]jdrch[/MENTION]

- LineageOS 14.1 - User confirmed by [MENTION=5909804]jdrch[/MENTION]

ADOPTABLE STORAGE UNAVAILABLE

Devices

Generally speaking, it regrettably appears no Samsung or LG device or stock ROM supports adoptable storage.

- LG G5 - Android Authority

- LG G6 - Tested in Verizon store by [MENTION=5909804]jdrch[/MENTION]

- LG V20 - Tested in Verizon store by [MENTION=5909804]jdrch[/MENTION]

- Motorola Z2 Force - Owned by [MENTION=5909804]jdrch[/MENTION]

- Samsung Galaxy S5 - Owner confirmed by [MENTION=5909804]jdrch[/MENTION]

- Samsung Galaxy S7 - Android Authority

- Samsung Galaxy S8 Plus - Tested in Verizon store by [MENTION=5909804]jdrch[/MENTION]

ROMs

Generally speaking, it regrettably appears no Samsung or LG device or stock ROM supports adoptable storage.