[darkwizard42]

Start with your network (assuming you have at least a few senior engineers and your career is 4+ years in tech, you should have this via LinkedIn). You are looking for folks you worked with that are now at their 2nd+ job in their career with mostly smaller companies (generally start-ups, 5-100 full-time, 1-50 eng teams) or are now involved with venture capital/investing/anything that suggests they have exposure to smaller teams. These are the companies with high chance of having a contract role open either because they are growing too fast or they just have lots of stuff to build but don't necessarily want to/can spend time on hiring.

From there reach out and ask them for help and provide your skillset, goals (X length contract work with mobile focus), and see if they will help connect you further. Hopefully your resume and past experience with that connection help you get your foot in the door more easily.