Poshier is described as 'is designed for small retail business looking for truly affordable and full function point of sale (POS) solution for Mac OS X and Windows'. There are more than 25 alternatives to Poshier for a variety of platforms, including Windows, Mac, Linux, Online / Web-based and iPad. The best alternative is uniCenta oPOS, which is both free and Open Source. Other great apps like Poshier are ERPLY Point Of Sale (Paid), Lightspeed POS (Paid), PHP Point Of Sale (Paid) and Floreant POS (Freemium, Open Source).
uniCenta oPOS is a branch of Openbravo POS point-of-sale and is capable of running on displays from 800x600 upwards. Most known Openbravo POS bugs have been fixed and enhancements to hardware options, additional reporting and localization.
PHP Point of Sale (POS software) is an online point of sale system designed to help small businesses with POS tracking of customers, inventory and sales. This program works great for retail businesses that use cash, check or account numbers in their POS transactions