Useful, but has a way to go
Very good way to allow more than one user to access and modify the same spreadsheet, but is, as another reviewer wrote, "clunky", especially on iOS devices. Would be nice for iPhone version to support charts.
Update 4/28/17:
Not sure if this is an iOS thing or Google Sheets thing, but the ability to switch to the 10-key keypad is great!
DainBramage1 about
Google Sheets, v1.2017.142