Quick verdict
Choosing between Microsoft 365 (Office) (1B+ installs) and Google Drive (10B+ installs) usually comes down to workflow, not raw feature counts.
Microsoft 365 (Office), built by Microsoft Corporation, focuses on word, excel, powerpoint and pdf tools in one mobile app. Google Drive from Google LLC instead leans into 15 gb free cloud storage with docs, sheets and slides built in. The two products are similar enough that comparing them feature-by-feature, rather than spec-by-spec, gives you a clearer answer.
This guide breaks down what each app does best, the use-cases each was designed for, a clean pros & cons matrix, and three high-intent FAQs people search before downloading. Both are free to install from the Play Store, so the real cost is your attention and habit — pick the one whose workflow matches yours.