Don't fall for it, they lie

I came across a research app last year and decided to download and try it out. It involved capturing the information on my receipts from daily purchases I made. It was a trial session and I was to receive a voucher from this company once the 2 week trial was completed. I received nothing. 2 people emailed me back and forth with no success. What a complete waste of my time. Nobody replies to my emails, nor did I get my voucher for completing the research.