I have written an app I want to try out, but want to see if someone can help me get it signed so I can try it out. It helps you identify who is calling when its a number you don't know.
Please PM me if you can help. I can send you the source and then host the file. You can beta test as well
Just purchase signing keys yourself. They're only $20 for unlimited use.
You'll be hard pressed to find a developer who will sign your application with his keys. I'm sure it isn't, but if your application is malicious that developer would be responsible.