Below is the list of core functionalities, I can develop1. Build apps compatible with iOS 4.x, 5.x and 6.x2. Uploading/submitting app to iTunes App store3. QR Code/Barcode scanning4. Custom UI navigation 5. Integration of various Cocoa frameworks6. Use of custom fonts7. API/Web Services integration.8. Social media integrations like Facebook, twitter, YouTube, Linked In, Instagram, Picasa, Google +, etc.9. Location based services like Geo- fencing, geo-location, User Tracking etc.10. In App purchase integration11. IAd, Admob, etc integrations12. APNS/Push notifications, local notifications, etc.13. Take photo from camera functionality, Choose photo from photo gallery functionality14. Core data migrations15. SMTP mail integrations, like Gmail, yahoo mail, etc.16. Core plot functionality for graphs17. Git hub integrations18. Managing ePUB files19. Integration of Airprint functionality20. Convert data/content to PDF, word, excel, formats21. Google analytics, Flurry analytics22. Adding even