Dear sir
I read your job description carefully and I think I’m very qualified.
I’m Android Senior Developer.
I have rich experience of Android app develop for 7 years.
I can do it perfectly and no problem.
if you want, I can show you android apps I've done.
If you select me, I will show you my best skill and my effects.
I can deliver high-quality result to you, fast turnaround time.
Thank you for the opportunity to submit my proposal for your project.
Best regards.