Dear Sir/Madam,
I am interested in developing your application natively for Android or with Flutter cross platform and would like to hear more about what it involves. I would be happy to discuss the project further with you if you are interested and to answer any questions you may have about my experience. Do you have any documentation which you could share to better understand your requirements?
I am currently working as a freelance mobile developer in a digital nomad lifestyle, in the past I have worked for an Australian company and a German startup in full time positions developing mobile applications. I have over 5 years of industry experience and over a year of freelance experience as a native Android developer both with personal and contracted projects. I could give you some examples of my work and if necessary I can provide my CV for you. I look forward to hearing back from you soon.