POS for mac and portable device with syncro with magento

Hello, i need to create a software for my business. I am a owner of a e-commerce and i need a solution that can permit to manage easily the my ecommerce based on magento with sales report stock management and sync of products, customer, orders etc. from the magento to the software and viceversa. I need that it have also a easy system for the sale in the physic shop with the update of stock also on magento. Pratically a complete POS. I need that it have a pretty and easy design and that is retina ready. If is possible to use the function of POS and other also on a mobile device could be great.