You need to first install the iPhone Mobile App from the App store http://www.zoho.com/projects/help/subscribe-iphone.html
Yes, you can use your Google ID to access Zoho Projects app on iPhone.
Follow the steps given below to use your Gmail ID:
After resetting the password, you can use your Google Apps mail ID as the user name and the password you recently set, and login to Zoho Projects on iPhone.
Yes, we support Android Mobile App. To install the app click http://www.zoho.com/projects/help/subscribe-android.html
Yes. Go to the tasks section, click the task name to view the task details page and click the Timer option.