I have a score from the IMSLP; it’s the Kodaly Sonate for Violoncello, op. 8. 21 pages long
When I try to open it in Newzik on either my iPad Air 2 or my iPhone 6s+ (latest version of iOS) it crashes. The first page shows up, and I see the thumbnails loading one by one across the bottom. When it gets to about the sixth one, Newzik freezes for a couple of seconds and then quits.
I open this file without problem in Adobe Acrobat Pro DC and in Readdle PDF Expert (latest versions of both), so it doesn’t seem to be an issue of file corruption.