Definately get an escrow and if you really want to give confidence to the investors, have the escrow only release the funds after specific milestones are reached.
This requires dedication and risk on your part as you will have to pay the developers in advance, but it will best protect the investors and will lead to a lot more confidence in your project.
Thats not a bad idea, how can I find a trustworthy escrow?
he is a much trusted person to keep him as an escrow for your project, he is currently working as an escrow of opair project . and maybe will have some other also.