For Android,
Information extracted from google forum - http://www.google.com/support/forum/p/Calendar/thread?tid=120533333cb7227c&hl=en
1. Press your device's < Home > button, then press < Menu >.
2. Select Settings and then Applications.
3. Select Manage applications.
4. Press < Menu >, the select "Filter."
5. Select "Running."
6. Select Calendar Storage.
7. Press "Clear data."
8. Wait for everything to re-sync.
Added by me since the multiple calendar did not show
9. Open android calendar
10. Click menu>more>calendars>ensure all multiple calendars are checked
11. Click ok
For IOS,
Just follow the instruction from http://michaelhyatt.com/how-to-setup-google-calendar-on-your-iphone-4.html.
Just follow the instruction from http://gigaom.com/apple/ipad-quick-tip-enabling-multiple-google-calendars/
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simply navigate towww.google.com/calendar/iphoneselect from the Safari Browser on my iPad. From here I can see all of my Google Calendars and I can select which ones to sync with my iPad.
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