Welcome to Just Answer. I am here to help you resolve your tax and finance concerns. Please feel free to ask anytime you need extra help.
First, I need to make you aware of a few items:
No matter that you call the money received from individuals/sponsors donations, if they receive any item in exchange they have made a purchase and you have made a sale which will be reported as income by your entity.
If you reside in California and work in California the state will consider this a taxable entity in California regardless where it is organized since it will have nexus in the state. The minimum franchise tax in California is $800 per year. To avoid duplicate taxation as well as the registered agent fees in Delaware ($200 + per year - one of the things not always mentioned) I would form the LLC in California.
Taxation of the entity will be fairly simple. Reporting form decisions will need to be made - either taxed as a C Corporation or a partnership. The partnership will provide you tax losses during development but your associates may not be able to take advantage of them.Therefore, I would elect to have the entity taxed as a C Corporation. The following link will take you to an IRS page about LLC's and there are other useful items referenced on that page which I suggest be read by you and your associates:
Your income would be taxed in California. If you finally determine to form the LLC in Delaware you will be taxed by Delaware as a non resident and will be able to claim an offset on your California return. It would , however, require two returns be prepared for you.
Your title does not matter if questioned by the IRS. The reality of the situation is what will dictate. Based on what you have stated, you will be an owner and, if C Corporation tax reporting is elected will be able to receive a salary. If taxed as a partnership you will not get a salary but will be taxed on your entire share of the profit/loss whether or not you remove it from the business.