Where will a two people company do business?

I'm planing to startup a company, that will operate online, with one more person. We are not from the United States but we would like to incorporate it there. Maybe Delaware or California, we are not sure yet.

The problem is that my partner is more likely to stay in her country until we get some traction and she can move to the United States too. If this is the case, where is the company going to be doing business in? The "headquarters" would be located in the United States but I'm wondering if we would have to incorporate the company as well in her country.

If this is the case, do we have to pay double taxes?
Would it be better for the two of us to be living in the state where we incorporate the company?

I think for people to be able to answer the double-taxation clause, they may need to know which country you guys are originally from as this may vary from country to country.

I am writing this answer assuming that your country has laws similar to my country - India. Considering it is only the two of you, you can get into an arrangement with the company that you incorporate - such that you are hired consultants in your own country. Remember that a company is a separate entity from the people who own it. (If you are registering a partnership, then this may be different).

So, the company will pay taxes on the profits it makes in the US as per the US tax laws.

You and your partner will pay taxes in your own country on the salaries you draw.
This salary will be deducted from the profits of your company - so technically, you do not pay double taxes.

When you grow to a larger number of people in your own country, you may need to register a subsidiary to the parent country. The parent company will pay the subsidiary for the services rendered - which then pays salaries to its employees locally.

If you do not want to go the subsidiary route, you can register a new, non-affiliated company in your own country which simply outsources services to the first company - the US one and thus gets paid.

In all these scenarios, you generally will not get taxed twice.

Disclaimer I am not a lawyer and not an expert on such legal and especially taxation issues. My answer is based on my own experiences.