Layout map in PDF form labeled Y210-0010; the dash has been garbled into odd characters by an encoding error in the file name. The name does not state the brand or device, though Y210 may refer to a handset model code, which you should confirm against your board. A layout map shows where components sit on the PCB, so it is used to find parts named in a schematic, locate test points and isolate shorted areas. At 201 KB it is a compact document, so check that its silkscreen labels match your board before relying on it.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @mobileshematic. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.