[Lenovo Legion Y700] leminhnguyen0703:
Torn between the 12-256 and 16-512 variant Legion Y700 2023 version, I decided to go with the 12-256 variant as it was more economical and 12GB of RAM atm is the sweet spot for flagships. With my specific use case and given how close to AOSP Lenovo ZUI is, I decided to try using my SD card as internal storage. Personally, I believe the advantages of increasing available storage space by setting up the microSD card as internal storage is minimal in comparison to the user experience of adopting UFS internal storage. This is only applicable to my specific needs, therefore your mileage may vary.

TLDR:

- The internal storage of the Y700 is faster than the fastest currently available microSD card on the market by a huge margin. The option to format microSD card as internal storage (i.e. Adoptable storage) has been optional to manufacturers since ~Android 7 in 2016 for a reason.

- Adoptable storage is Android's method of making a part of (partitioning) the inserted microSD card available for app storage. As of now, there are more cons than pros for doing this.

- The only reason I wrote this guide is for my specific use case: Spotify keeps removing and forcing a redownload after every reboot. The only solution is to setup Spotify to download onto an adoptable storage partition for local listening. This may be applicable to other apps as well, but I cannot guarantee its success.

- I AM NOT RESPONSIBLE FOR ANYTHING THAT MAY OR WILL HAPPEN TO YOUR DEVICE AFTER ATTEMPTING THIS PROCESS.

DISCLAIMERS:

1- The option to format the microSD card as internal storage (one of two choices upon inserting a microSD card on ZUI 15) has often been disabled on modern devices released in the past few years, therefore no support will be given. Not every apps are compatible and bugs are bound to happen. Prepare to redownload every apps & their data that have recently used your SD card again.

2- This process will wipe everything on your SD card and create a partition used by Android for internal storage. Do not attempt this if you do not understand what this means.

3- Always use the best possible SD card within your budget (numerous reasons why and countless more).

4- Once again, only attempt the following steps when you are fully aware that (1) YOUR DEVICE CAN BE BRICKED (2) YOUR WARRANTY MAY BE VOIDED (3) FUTURE UPDATES MAY RENDER THE CURRENT SETUP USELESS AND YOUR DATA UNRECOVERABLE.

INSTRUCTIONS: Now that you've read and understood the above disclaimers, here it is step-by-step:

1- Enable ADB Debugging

2- Enter these commands

adb shell
sm set-force-adoptable on
sm list-disks
sm partition disk:xxx,xx mixed YY

xxx,xx = SD CARD ID found in list-disks (should be 179,xx)

YY = percentage of sd card you want to use as internal storage (EX: I have a 1TB card and wish to use 250gb as internal -> YY=25)

sm list-volumes

(If there is a sector titled private:xxx,x mounted xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx then you've succeeded)

3- Reboot

4- Settings -> Apps. Go to each individual apps -> storage & cache -> Storage there should be an option under titled Change. Use this to migrate the apps from your internal storage to the newly-created to your SD card. You willl have to do this indivually, with each app. DO NOT ATTEMPT THIS WITH 3RD PARTY APP MANAGERS AS THEY DO NOT PROPERLY RECOGNISE THE DATA AND CAN CAUSE BOOTLOOPS.

5- Enter each app that have been moved to make sure they can load properly. If they don't, you have 2 options:

- Uninstall and reinstall the app. These newly installed app should be installed on your SD card and load properly

- If the app does not load, follow step 4 but move them back into internal storage and try again.

PROS:

1- Spotify music files I've downloaded will always prompt a redownload after reboot. when downloading to the SD card. They've been aware of this bug going back multiple major updates to their Android app and haven't (or unwilling to) found a solution. The only available option to the common users is to set the app's download location to an an adoptable storage parition on the SD card. Numerous redownloads of my~60GB Spotify playlists caused me enough annoyance to even attempt this process in the first place.

2-

Little

space saving for games. I thought that migrating my most resource-intensive games to the SD card would free up my internal storage. Turns out, online games that requires constant updates and resources caching will always download their resources to the internal storage.

3- Options: Android is open-sourced afterall and It's your device. Do with it however as you please. I have debloatted, modded, bricked and recovered my past and current devices (S23 Ultra and Y700) to hell and back and you should have the choice to muck around with it as you please as well.

CONS:

1- User experience is the main reason why OEMs stopped including a microSD card in their flagship. The fastest currently available microSD card on the market is still slower than the earliest available version of UFS.

2- Lenovo leaving the option available in their ROM does not mean it is stable. Settings or 3rd party apps not will show proper amount of storage used.

3- App incompatibility. I have an app that outright refuses to start after migrating to SD card, yet continues to operate normally after migrating back to internal storage.

4- Potentially slowever startup time. I've experienced this with only 2 apps, but YMMV.

5- Unofficial support: There was no problem upgrading via OTA from ZUI 15.0.677 to 15.0.723, but there's no guarantee the current method will work for future updates. If you lose unrecoverable data, you're straight out of luck.​