This is a recurring street photography gig to help promote a new photo sharing app.
Check out the iPhone app https://apple.co/3NRXHyw and/or the Android app https://cheez.cc/45Di08N
You'll be approaching people on the street, asking them to take free professional portraits (and/or group pictures of them), and giving them a card with the info about the app, which they'll be able to download to get the pictures.
You must be an experienced photographer (professional or hobbyist)
You must have an iPhone or modern Android
Ideally you have your own DSLR camera