XiaoYuReader app for iPhone and iPad

This software is designed for digitally signing pdf documents, handwritten annotations, users can easily add their own stamp image to pdf document and add the user certificate information to the electronic seal, the signature can be validated by Adobereader reader.
This software also provides a message is sent, users can easily send the signed document to pdf good e-mail.
After other App can call this software, open the corresponding pdf file, and then handwritten signature or signatures. Examples are as follows:

NSString *filePath = [NSHomeDirectory() stringByAppendingString:@"/Documents/test.pdf"];
documentController = [UIDocumentInteractionController interactionControllerWithURL:[NSURL fileURLWithPath:filePath]];
documentController.delegate = self;
documentController.UTI = @"com.adobe.pdf";
[documentController presentOptionsMenuFromRect:CGRectZero inView:self.view animated:YES];

Premise, pdf file must exist.