Pros
The app is incredibly user friendly, you can set up your profile and start seeing shifts immediately. Your contacts at HYR are very supportive and will answer any and all questions you may have along the way. You can filter which jobs you see based on minimum hourly rate, which is fantastic, and you are paid within 3 business days upon completing a shift.
Cons
Definitely supplemental income, BUT the more experience you have (ie retail, security, bartending, cashier) the more work you can find/will pop up.