No, the software doesn't work with the versions of MAC OSX listed above because their official website discontinued. Apps that have their homepage discontinued are not compatible with latest versions of the operating systems. There is also no report or news regarding the future availability of Poshier application.
However, there are other alternatives available:
- uniCenta oPOS
- Gazelle Point-of-Sale
- Floreant POS
- POSper
- Openbravo POS