While you can create taxes on the device, it's just as easy to create and apply them on the device. In the Catalog section of Poynt HQ (https://poynt.net/catalogs), there is a link for Taxes on the left hand side of the screen.
In this screen, you can create taxes, assign them to catalogs, edit or delete them.
To create a tax, click on Add Tax button on the top right hand corner. In the pop-up, enter in the necessary information.
After you hit Add Tax, this will appear on the list of taxes.
NOTE: At this point, the tax has simply been created, but not yet assigned to any particular catalog.
To associate a tax to your catalog, go back to the main page of Catalogs and click on the one you would like to add the tax. Click on the Tax link just above the product squares.
Click on Add Tax when prompted. In the box that appears, choose Create Tax or Existing. In this case, since we've already created the tax, we'll choose from the existing list.
Once you click on Add, this will associate the tax with this particular catalog. This tax will be applied to all products in this catalog going forward.