Where can I find help with a business name and branding?

I have created an app, and am stuck on choosing the name, because the one I was banking on, is already trademarked. My developers are great, but I feel like they lack creativity and are unhelpful in this area. I’m not really looking to pay for a whole marketing package with a fancy company, just to get some advice from someone in marketing on which name to choose. Thanks for any advice.