Building an Android application can take anywhere from a few weeks to even months or more, depending on the complexity of the app and the number of features. Simple apps with basic functionality may be completed in a few weeks, while complex apps with advanced features and integrations can take 3-6 months or even longer. Factors like the UI/UX design of the app, third-party integrations, and the experience of the development team also affect the development time of an Android application.