There is no evidence that mathematical semantics cannot be understood due to blindness, the problem is the current access barrier to mathematical resources. In light of this problem, this survey aims at providing visually impaired persons (VIPs), or people close to them, with an overview of the currently available software tools for approaching mathematical content. These can be categorized into (a) tools for accessing mathematical documents (where VIPs are just consumers of content), and (b) tools that allow VIPs to become the creators of mathematical content and even to execute mathematical operations. We also explain the advantages and disadvantages of several key technologies used to interact with mathematics. Moreover, we discuss the necessity of the most common formats and languages behind these tools. Finally, we outline promising paths for future research and development towards blind-friendly mathematical resources. The authors hope that this survey may encourage researchers to engage with the still unsolved challenges of this topic.