Social Media Messaging App Development

I'm looking for an experienced mobile app developer to create a social media app focused on messaging. The primary feature will be messaging, with additional functionalities like group chats, voice messages, and media sharing.

Key Requirements:
- Messaging as primary feature
- Group chats, voice messages, and media sharing as additional features

Ideal Skills and Experience:
- Proven experience in developing social media or messaging apps
- Strong expertise in mobile app development (iOS and Android)
- Knowledge of real-time messaging protocols
- UI/UX design skills for an intuitive user experience
- Ability to integrate multimedia sharing capabilities

Please provide a portfolio of similar work and an estimated timeline.