I used to have option to chsnge storage area eg from internal to external card on my Samsung gs5. I would open App Mgr and do this after downloading apps and periodically.
What the hell happrned.. since TMOBILE store tech removed my stars card and btw list it with years of photography and precious persinal.phOtis on it. When he switched the Samsung ext storage card that was corrupt. Installed new Samsung Micro sc, now there s no option in app Mgr to move anything..what could have he done? ??
Well, it depends now on the OS they may have altered something. You need Android "Marshmallow" to have apps on a SD card.
And I have to say, that they should have known better than to cause that. Me, I would be complaining to them. But that is me. They should know to check the phone to make sure the card is not set as internal storage before doing any work to it. If it is set to that, give it to you to remove anything you want off the card before they convert it back to external.
See when the card is made "internal" storage it is formatted and encoded to that device. If they "Hard Reset" it or anything similar, the device would no longer recognize the cards data. Making all that was on it inaccessible.
You will need to format your new card to be "Internal" storage, rather than "External" to be able to put apps on it again.
How to turn external SD card into internal storage on "Marshmallow".
NOTE: Please be sure you start with a blank SD card. It needs to be blank because when the card is converted to "Internal" storage, it will be formatted (wiped) and encoded (making the cards data only readable by that device).
1. Go to device “Settings”, then select “Storage”.
2. Select your "SD Card", then tap the “three-dot menu“ (top-right), now select “Settings” from in there.
3. Now select “Format as internal”, and then “Erase & Format”.
4. Your SD Card will now be formatted as internal storage.
5. Reboot your phone.
NOTE: If you don't reboot the phone, many things may not work correctly, so make sure you do.