Hello, thanks for ask. Well, in the Web are specialized sites for coders, developers and testers. I reccomend you the three I consider best for your searching:

1.Toptal: It matches the a good percentage of freelance developers with employers. Based on your project description, you will be matched with the developer most suited for the job. You will then have two weeks to decide if they are right for you.
2. Matchist: This site connects top freelance developers with entrepreneurs and startups. You submit your project, and they will give you three great developers from which to choose. Matchist accepts only 15 percent of developer applicants to their network.
3. Guru: Guru allows you to look for specific services and people who provide them. These include general programming, language-specific programming, software, and management.

I hope this info would be useful for you.

Greetings.

Having managed platform and app development teams over the past 20 years at my startup-focused brand development + marketing agency, I tell you that it can be a tough road for entrepreneurs and early-stage startup founders without an intense technical background...it can be downright frustrating, and even crippling to new startups in build mode, just trying to get off the line.

But, if you try to go it alone (I don't recommend isolating these types of teams from an overall, cohesive brand and marketing strategy), be sure that you're working with a senior team, with significant experience in the areas you're focused in. In other words, don't try to build a consumer marketplace type of business with developer(s) who have only worked in banking or finance. And don't bring on programmers with little experience in consumer brands that have only worked in biotech.

Also be sure you have a well-versed, senior lead/manager watching over the team of developers, as it's important to have someone to help keep the requirements, concept, and overall work moving forward cohesively. This will reduce your headaches and frustrations significantly.

Lastly, always be sure you have access and ownership over the code, even as it is being developed...if you don't, you get yourself into a sticky "hostage" situation if you find your work slipping grossly behind schedule and decide to pull the plug on the team entirely.

If you have any more questions on the matter, happy to discuss any time so feel free to reach out!

Hello, as someone usually on the other end my advice would be to first start with credible sources. These can be some of the gig platforms like Guru and Upwork. However, you may want someone more local in which case search for a local developer meetup. Contact the group and ether go to a meetup and meet some of the companies and independent developers or ask them to announce/post an ad for you in their group. Doing this will get you known local developers with a good reputation. It is always best when possible to have someone you can meet with face to face and see the same thing on the same screen. With that I would recommend that some of your requirements for taking on a team or developer is that they use a source control system like git, offer frequent updates (weekly or bi-weekly) on the status of the project and who have examples of previous work along the lines of what you need done.
As someone who has bid and applied for positions like yours I would be happy to help you evaluate teams and developers for making your choice and even help you locate some in your area.