I seriously thought of making this app myself a while back, and came up with a list of features I would include. Here are a few others that come to mind.

Multiple locations per reminder - e.g. notify me when there is a Bank of America and a post office within walking distance of each other.

Date/location reminder - e.g. notify me if I pass a Bank of America during the last 5 days of the month.

Time/location reminder - e.g. only notify me if I pass Bank of America during bank hours