[Android Q&A, Help & Troubleshooting] pndwal:
Here is info I previously posted on this:

post #5140

Oct-N utilises adoptive SD storage properly (unlike marshmallow), allowing most downloaded apps to be moved to SD (app developer dependant) in FULL, along with all user data. - No more need for link2sd or apps2sd when running out of space for apps! (This is the best feature for me. Recommend fast SD card for phone-mem-like performance. I use 80MB/s SanDisk Ultra 64GB SDXC. One app not to move: ES file Explorer if you use root explorer [Loses root explorer permission when on SD card].)

. . . updates now retain all settings . . . so no longer need to . . . restore saved adopted storage encryption key in order to use SD data. (I'm still saving this for my peace of mind however. Key in data/misc/vold).

Post #5695

I no longer use App2SD since N. Format SD as internal, migrate data (frees up phone memory for system and system apps only basically), moveable apps automatically go to SD. Problems with this in M gone. If Dev hasn't enabled 'move apps to SD', can 'Force allow apps on external' in Developer Options (Makes any app eligible to be written to external storage, regardless of manifest values). Seems perfect out-of-the-box solution for low memory phone!

Post #5708

(You need to migrate) data to SD. As I mentioned, this will free up phone memory for basically system and system apps only.

Go to settings, storage, SD card, 3 dot menu at top - and select Migrate data to move data from internal to SD.

Then go to Internal storage, Apps, and individually move any apps that have CHANGE button that haven't been moved automatically. Newly installed apps will be installed automatically on SD if developer supports SD installation.

If Devs haven't added 'move app to SD' support for some apps (and you want to move more), you can still move them. Go to Developer Options, select 'Force allow apps on external' in (Makes any app eligible to be written to external storage, regardless of manifest values).

In a standard file explorer (and with usb mtp computer connection) you will now see only your SD card, which is now your phone (user) memory (ie user data partition), and this has changed to the capacity of your SD card. It doesn't show up before migrating data, even though formatted as internal, as user data partition needs to be swapped to it from internal and the migrate data process does this. That's why there is no longer any internal phone memory showing. (It's now freed up for basically system data, system apps, and unmoved user apps.)

Post #5727

Dont forget, for good results you need a fast SD card. I use 80MB/s SanDisk Ultra 64GB SDXC, but faster would be better.

Also, if Devs haven't added 'move app to SD' support for some apps (and you want to move more), you can still move them by selecting 'Force allow apps on external' in Developer Options. (Makes any app eligible to be written to external storage, regardless of manifest values).

On another device (Lenovo tablet) I still use Apps2SD to integrate system updates into system (convert to system app). Frees up internal memory as updated app as well as original (deactivated) are otherwise retained. [I tried a stand-alone app (System cleaner 2) to do this recently, but it messed up system apps. Went back to Apps2SD for this, and it integrated updates without problems.] I intend to do this maintenance on y550 also when needed. (Apps2SD has other functions still useful to, eg. Fix Device Lag (Trim partitions), etc.)

(See also post #5698)

Hope it helps, PW