Just a quick word of advice...
If you are just starting out and are in MVP stage, and unless you have huge investment upfront for scalability and you product is already tested, i would not go straight to the "big company" to build it, i would go for upwork.com for some freelancer first to build a primary version of the product and start it out like that. Then when it takes off, invest big in scalable way expanding the thing.
Hope that helps.
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Email me and we can start a conversation concerning your needs!