How to send a PDF file using UIActivityViewController

try this

NSData *pdfData = [NSData dataWithContentsOfFile:pdfFilePath];
UIActivityViewController *activityViewController = [[UIActivityViewController alloc] initWithActivityItems:@[@"Test", pdfData] applicationActivities:nil];

[self presentViewController:activityViewController animated:YES completion:nil];

and also

NSString *str = [[NSBundle mainBundle] pathForResource:@"AppDistributionGuide" ofType:@"pdf"];   
UIActivityViewController *activityViewController = [[UIActivityViewController alloc] initWithActivityItems:@[@"Test", [NSURL fileURLWithPath:str]] applicationActivities:nil];