A google spreadsheet as backend example
https://andregumieri.github.io/yard-sale-example/
The spreadsheet: https://docs.google.com/spreadsheets/d/14zox-ptRriyVgYz8796cIaZm52t1zvroZUTSczlRqbM/edit?usp=sharing The images folder: https://googledrive.com/host/0B-wo61m8bE0Hd1pETGEwS05Wdmc