Secure Online Banking App Development

I need a developer to create an online banking app focused on account management. The app should include:

Essential Features:
- Balance checking
- Transaction history
- Account alerts

Security:
- Two-factor authentication

Ideal Skills:
- Experience in developing secure financial apps
- Strong background in implementing two-factor authentication
- Proficiency in mobile app development (iOS and Android)

Please provide examples of similar work and your approach to ensuring app security.