Android's Google Docs editors -- Docs, Sheets, and Slides -- give you mobile access to Google's collection of productivity apps.
Free: Google's Docs apps are free, and with them you can create text-based documents, spreadsheets, and presentations.
Cloud storage: You start with 15GB of free Drive cloud storage. Jump to 100GB for $19.99 per year or 1TB for $99.99 per year. Gmail messages and Google Photos can count toward your cap. All files are stored on Google's Drive servers.
Share and collaborate: Give access to a file by tapping the Add People icon and adding collaborators. You can set whether they can edit, comment, or just view the file. Users can add comments to a file and address comments made by others.
Works with Microsoft Office: You can import and convert Office files to Google Docs files. Through the Chrome browser version of the apps, you can use Office Compatibility Mode (OCM) to work on Office files in their native formats.
Templates: From a resume or a status report to a travel planner, the Google Docs apps offer 70-something nicely designed templates to give you a head start on creating a document.
Add-ons: Extend the functionality of Docs and Sheets through add-ons. While the browser versions offer dozens of add-ons, you can add a few to the mobile apps, too, centered on business and education uses.
Word processing: Docs, the word-processing piece of the Google Docs apps, lets you create, edit, and format a document. The Android version gives you text and paragraph formatting tools similar to those of the Web version. You can add links, images, and tables; view an outline of your document; run a spelling checker; and check word count -- all from your phone.
Spreadsheets: The spreadsheet app, Sheets, lets you create, edit, and format a spreadsheet. You can also import data sets and Excel spreadsheets into Sheets. You can create charts and graphs and use built-in formulas. Based on the data in the spreadsheet, the app can suggest charts and analysis through its Explore tool.
Slides: Slides is Google Docs' presentation app. You can build slides on your phone and work with text, shapes, and tables. And you can drive your presentation from your phone, presenting via Chromecast to a monitor or through a Google Hangouts video chat.
Sidekicks: In addition to its trio of Docs apps, Google has companion apps that extend Docs, Slides, and Sheets: Keep for taking notes, Drawings for charts and diagrams, Forms for survey and forms, and Sites for creating webpages.
Lacks parity with browser version: While the Android apps are surprising useful, they lack a few features found in the browser apps. For example, while the browser versions let you chat with others in a file, you can't see or participate in chats on Android. To see the revision history of a doc, you need to use the browser version of the apps. And creating and using pivot tables in Sheets require the Web version.
Few advanced tools: The apps lack some high-end capabilities found in a paid productivity suite such as Microsoft Office. If you need to work with thousands of rows of data or to index hundreds of pages of a report, you might need to look elsewhere.
Unless you need a spreadsheet for huge amounts of data or you're writing a novel, Google's free and collaborative Android apps should meet your needs.