Android technical writer (technical writing)

Greetings, We are looking for a smart Android technology expert AND technical writer with deep experience of the Android platform as well as good writing skills. We will need this person to write for my org. several (probably around 10, spread over several months) technological articles about the Android platform. The content of the articles and the technologies covered will be dictated by my organization. The writer will need to perform additional (web) research to complete the relevant material and write the actual article. We are willing to pay $80-$100 (depending on quality) for a well written article. Again - our writer must be an expert of the Android platform. We will need to see prior articles of our candidates. Steve