My professionalisms are : 1. Native iOS & Android development with swift/objective-c/java/android 2. Video/Image processing with FFMpeg, AVFoundation, GPUImage, CoreImage, CoreGraphics 3. VoIP with WebRTC, SIP, Quickblox, OpenTok, Sinch, Linphone 4. Chat app with Xmpp/Openfire, Xmpp/Ejabberd 5. Geolocation app 6. Video/Audio streaming - Wowza, webrtc, icecast