Matlab is good for fleshing out system performance and designing system mockups prior to prototyping. It is *NOT* viable for production systems.

Matlab is really good for the following:

* Imaging problems/systems
* Control systems and design (simulink)
* DSP, filters, and linear systems
* Physical optics and light propagation

Matlab is ok for:

* Machine learning/classification problems
* GUI 
* Regression problems

Many companies use Matlab, especially for optical system/image processing mockups and control systems. I personally used it a for a contract with a large orange grower for a fruit defect grading prototype (in addition to C++ and other optical modeling design software like FRED, ZEMAX).

Your biggest issue will be finding clients, but Matlab is particularly prevalent in the **aerospace, defense, electrical engineering, applied mathematics, and optical engineering** communities.