Hello!
What type of application are you talking about? Do you have a current interface or it will be the first interface for the application? I work in Adobe illustrator. So no matter what the device is or what the resolution is, you will always have all the suitable resolutions (in your case android and iPhone). Vector graphics of illustrator backs us with this facility. If you want any sample for your application, I can provide you one for free. For that I need you specifications about what you want in your sample. If you like my work, we will proceed, otherwise you may chose another designer.
Regards.