Developing an Android app is a relatively large project that involves downloading several pieces of software and becoming proficient in their use before proceeding. The task also requires plenty of prior planning and preparation, such as learning how to design an elegant user interface and how to handle user input.
Almost all Android apps are designed using Android Studio, a proprietary piece of software that was designed especially for use by amateur programmers. It features a project wizard to allow new users to get started with basic code quickly, and it also allows for development across numerous devices with multi-screen app development.
As well as Android Studio, developers keen to develop apps of their own also require the Android Software Development Kit, also known as SDK. Both pieces of software are relatively simple to use from a programming perspective, but may be difficult for beginners to grasp.
Fortunately Android's policies on device provisioning and the submission of apps are more open than those of Apple Inc. and many step-by-step software tutorials are available directly from Google, the primary developer of the Android mobile operating system.
Beyond training and competency in how to use programming software, the only other considerations to make are obviously what the app does, what it is for and considering if it is financially viable. Common business considerations include whether or not the app is useful, if it has any appeal to a large enough user base or how long the app may be relevant.