Business Insider/Julie Bort President, Google At Work, Amit Singh

Ten years ago, Google declared war on Microsoft Office by offering a cheap alternative on the web, Google Apps.

Flash forward to 2015, and the company has big plans to grab 80% of the users at Microsoft's biggest customers.

In 2005, "The whole industry looked at us like we were crazy," Rajen Sheth, a director of product management for Google's Enterprise team who worked on those early products, told us.

They don't think that way anymore. 2014 was a breakout year for Google in convincing large enterprises to use its email, word processing, spreadsheets, presentations, cloud computing, and cloud storage.

And we ain't seen nothing yet.

Amit Singh, president of Google for Work just shared with us his plans to elbow its way into Microsoft's turf and walk away with, he hopes most of the users at large companies.

"We’re ready for them now. I think the last 12 months we’ve proven to a) ourselves b) the market that the Apps are ready for adoption in large enterprises. Now I think is the time to actually scale that even further," he told us.

The plan is simple but ingenious.

Step 1: Make sure that the apps Google offers have "85-90% of the functionality" of Office.

"And in some cases new functionality ahead of the curve. I mean realtime collaboration in Docs, there’s no equal to that. Office Web Apps is a poor proxy for that," says Singh.

Step 2: Don't worry about the remaining 10-15% of the features required by power users, particularly Excel.

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Business Insider/Julie Bort Google director of product management Rajen Sheth

Excel blows Google Sheets out of the water in how much data it can handle and how it performs sophisticated financial analysis.

Singh doesn't care about that because, he says, only 10% of a company's employees need or care about that stuff.

Because Apps is hosted on Google's cloud, Google can see how people actually use productivity apps.

Note: Google PR tells us that this statistic comes from a company called Softwatch who offers a service that lets companies monitor their Apps usage and not from Google's internal monitoring.

It turns out, that most people aren't even creating new documents or spreadsheets at all.

"Most people are reading and doing very light editing — our analysis has shown us that," he says. "If that’s the case, why would everyone always have to have Excel, etc.? You have lots of users and you don’t have to license them all for Excel or Office. That population of creators and content authors is 10% or less."

Step 3: Support Office documents as a "first-class citizen."

With Google's cloud storage service, Drive for Work, people can upload Office documents and when they open them, they automatically open in the appropriate editor in Google Apps on your desktop, phone or tablet. You do not need to install another app to open Office files.

They open in an Office-compatible editor, QuickOffice, which Google acquired a few years back. QuickOffice "will render [Office files] perfectly (or nearly perfectly) so you can do light editing and share it back, in native Office format," says Singh.

Step 4 (and this is the brilliant part): Don't try and convince enterprises to convert from Microsoft Office to Google Apps.

Google knows there's very little chance that companies are going to wake up one day and throw Microsoft Office out completely. Instead, Google wants them to buy Apps in addition to the Office licenses they already have.

This may sound like doubling up. Why buy Apps if you already have Office?

But Singh believes the double-use will only happen for a short while. In the end, companies will stop buying new Office licenses for employees who don't really need it.

"So give people an option and overtime reconcile your associated licensing on actual usage, not just on some upfront commitment and some long-term contract. That’s the old world of enterprise software. Today you should just pay for what you actually use, not for some arbitrary number of users," Singh says.

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