Add 'Open in ...' button in Safari

Register File Types your App support:

https://developer.apple.com/library/ios/documentation/FileManagement/Conceptual/DocumentInteraction_TopicsForIOS/Articles/RegisteringtheFileTypesYourAppSupports.html




to support PDF and ePub, add the following in info.plist
<key>CFBundleDocumentTypes</key>
<array>
    <dict>
        <key>CFBundleTypeName</key>
        <string>PDF</string>
        <key>LSHandlerRank</key>
        <string>Alternate</string>
        <key>LSItemContentTypes</key>
        <array>
            <string>com.adobe.pdf</string>
            <string>org.idpf.epub-container</string>          
        </array>
    </dict>
</array>