The best logo design software is graphics software, and that doesn't necessarily mean Photoshop.
Logos, even if text-based, are ultimately graphics and graphics software is the right tool for the job.
We have so many software available to design logos but Adobe Photoshop, Corel draw and Adobe illustrator are the best tools to design a professional logo.
The most essential thing for any company or company is an emblem which must be unique and recognized by the customer about that particular company or company. Moreover, company logo is extremely important part of any company to promote its business.