Correct. For the LLC, you need to file a corporate tax return and that requires TurboTax Business, which is only available for PC. Depending on your financial situation, you might think about buying a cheap windows computer for your business as a business expense, and use it for your accounting and tax software, or you might install Boot Camp or parallels on a Mac, in order to run windows.
As part of the corporate tax return you will produce a K-1 form for each of the LLC owners. The LLC owners will enter the K-1 on their personal tax returns along with other income, and their personal deductions and credits. This can be done using TurboTax online, or TurboTax for the Mac or PC.