[Wynton]

I've been happily using Mobile Sheets on Microsoft Surface Pro, but still long for a screen that allows me to read 2 pages of sheet music at a comfortable size.

My Surface is now 3 years old, has a small crack on one edge, and could use a bit more capacity for work purposes.  So I'm considering buying a new Surface, and it would be easier to justify the purchase if a second Surface could also address my sheet music reading needs.

Here's my question: if I have 2 Surface devices, can I pair them easily so that I can read the same 2-page score on the devices simultaneously, side-by-side?  In other words, I want to read page 1 on one device, and page 2 on the other device.

Another option is to just buy a monitor of some kind.  If I do that, can I pair it with one Surface in the same manner?

[McAroni]

If there is MobileSheets on both devices then you connect them and you could select the Mode how the devices interact. The "book Mode" is that what you are looking for. 2 pages side by side.
See also full manual page 150.

[Wynton]

Can book mode be used if one device is windows-based and the other is Android?

[McAroni]

Never tested it but i think this will work. the two devices should be in sync and the same library sould be in use.