If i roll back to 8.1 from Win10,will my personal data and app will be deleted....??

[Utkarsh Gajera]

...

 

[charlatan1978]

Yes it will.
As long as apps are backed up they will download once 8.1 loads.
However game saves will be lost.

 

[alb3530]

Application data (such as settings, and so on) is only included in backup if the developer of that specific app has explicitly implemented support for that.

Most applications don't support it.

For example: Instagram will require your login when opened, and most applications will behave as if they are being installed for the first time.

Best regards

 

[charlatan1978]

You didn't mention what model phone you had.
If you have an SD card you can choose to keep the contents.

 

[xandros9]

You didn't mention what model phone you had.
If you have an SD card you can choose to keep the contents.

Do note that keeping the contents does not extend to apps installed on the card.

 

[charlatan1978]

Do note that keeping the contents does not extend to apps installed on the card.

Correct, I just meant music and pictures, etc.

 

[Utkarsh Gajera]

I m just going to roll back my L1320 to 8.1 and then i will install win10 again...

 

[Nightwolf88]

Correct, I just meant music and pictures, etc.

I m just going to roll back my L1320 to 8.1 and then i will install win10 again...

Just make backup to be sure.
I have no sd-card (lumia 1020) and everything is gone when i roll back!

 

[xandros9]

Just make backup to be sure.
I have no sd-card (lumia 1020) and everything is gone when i roll back!

Yes that is normal considering with an SD card-equipped phone, anything on main/internal memory is wiped regardless.

But still, a backup is a very good idea.