With the new Google Drive App for iOS and Android, you can create and edit Google Spreadsheets on your mobile device. Functionality includes font adjustment, column resizing, data sorting, and more. If you're collaborating in real time on a spreadsheet, you'll see other people's edits as they're made.
You can get the Google Drive App from Google Play or the Apple App Store.
For more details, see Google Drive Blog posting Edit spreadsheets on the go with the Drive mobile app.