Schematic PDF named simply AP2, 274 KB in size, with no device, brand or board number in the name. AP in phone schematic sets often denotes the application processor section, so this is likely one page group from a larger split schematic, but the model cannot be confirmed from the file name alone. Open it in a PDF reader and check the title block for the board name and revision. Use it only after matching it to the exact board, alongside the related sheets it belongs with.
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 @mobileschematicshub. 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.