Cross-Platform Social Networking App Development

I'm looking for an experienced mobile app developer to create a cross-platform social networking app for both iOS and Android.

Key Features:
- User Profiles
- Friend/Connection Management
- Real-time Messaging
- News Feed
- Photo/Video Sharing
- Notifications

Ideal Skills and Experience:
- Proven experience in developing cross-platform mobile apps
- Strong expertise in social networking app functionalities
- Proficiency in both iOS (Swift) and Android (Kotlin/Java) development
- Experience with backend technologies to support real-time data
- UI/UX design skills to create an engaging user experience
- Knowledge of app security protocols

Please include your portfolio and relevant project experience in your bids.