Secure Invoice Web + Android

I need a full-fledged invoicing solution that works in the browser and is paired with a dedicated Android app. Think of the overall polish and flow found in SleekBill or myBillBook, then add stronger data security and cloud-based sync so my team can work from anywhere without fear of losing records... (Budget: ₹12500 - ₹37500 INR, Jobs: Android, Android App Development, API Development, Cloud Computing, Database Management, Mobile App Development, MySQL, PHP, User Interface / IA, Web Development)