Hi, I’m software and database developer with more than 30 years experience in Delphi (since the times of Borland Turbo Pascal!). In the past 20 years I have worked (in-situ) for two international organizations (Inter-American Tropical Tuna Commission, in San Diego, USA, and the Food and Agriculture Organizations of the United Nations, in Victoria, Seychelles). I have experience working with Andoid and Firemonkey, and in fact, at this moment I'm working in a project that's similar to yours (i.e. scanning barcode/QR codes using ZXing+Delphi on Android. This is a re-development of a desktop application I wrote some months ago using the .NET framework) . If you think you may be interested in my services, please open a chat so we can further discuss your requirements.
Sincerely,
Marco García