You can also add delivery notes to the order. There's a freeform text box for them. I like to say things like "Please leave with Bell services" or "I'll meet you at the Pop Century Bell Services counter, wearing a rainbow-striped big floppy hat. Alternate phone number: XXX-XXX-XXXX. (Updated 1/17)"
The app has a moving map (be aware there are some delays in updating) and you'll get alerts when you're the next stop. Delivery drivers have pretty full schedules and tight timelines, so I try to be waiting for them, instead of expecting them to wait for me.