Zoho mobile's app for android and iPhone was updated today to allow sign-in with Google, Google Apps, and Yahoo accounts (the desktop version already had this) along with a redesigned home screen, the introduction of mobile Zoho Docs that is limited to viewing documents, and some performance tweaks. All of these are great improvements, but editing of any type of mobile document would have been a game changer. I have been expecting this feature from the Google Docs team but it hasn't arrived yet. Whoever (Zoho, Google, or Microsoft) introduces this feature first will definitely cause a spike in their number of users along with a drastic change in how we use our smartphones.
The New Mobile Zoho