In the contemporary landscape of technological advancement, the Android platform has emerged as a veritable colossus, commanding a sizeable chunk of the global OS market share. In such an environment, the need for proficient Android app developers has become a pressing necessity for businesses looking to expand their digital footprint effectively. The hiring of a skilled Android app developer, however, requires strategic forethought and a well-executed approach. I will outline here an elaborate step-by-step guide to aid you in this endeavor.

The first important consideration should be a comprehensive understanding of one's project requirements. Determining the fundamental objectives, recognizing target audience, and recognizing the key features and functionalities your app needs to have are paramount. It provides a clear framework in which you can assess the expertise of a potential developer. This understanding should be grounded in a profound analysis of market trends, user behavior, and competitive landscape.

Next, you need to determine the engagement model that suits your project. Typically, there are three models: freelance, agency, and in-house. Each model has its own set of merits and demerits. For instance, freelancers offer flexibility and cost-effective solutions, but may lack a broad skill set and reliability. Agencies provide a comprehensive range of services and are generally reliable, but they can be cost-prohibitive. In-house developers afford complete control over the development process but involve substantial overhead and management efforts. Your decision must align with your organization's capabilities, budget constraints, and the complexity of the project.

Once the engagement model has been ascertained, it is paramount to evaluate the developer's technical expertise. Android app development involves several technologies, frameworks, and languages, such as Java, Kotlin, and Flutter, and an understanding of Android SDK and APIs. Further, with the rise of emerging technologies like AI, AR/VR, IoT, choosing a developer with expertise in these areas could be an added advantage. This evaluation should not only be based on their claims but also on project portfolios, client testimonials, and potentially, a trial task.

In addition to technical skills, soft skills, such as communication, problem-solving, and teamwork, are equally important in a developer. These skills facilitate efficient collaboration, timely resolution of issues, and ensure a smoother development process. An assessment of these skills can be made through structured interviews and behavioral analysis. One may employ the Nash equilibrium theory from game theory here, aiming to achieve a state where both employer and developer believe they are getting the best deal, ensuring a stable and productive working relationship.

Alongside assessing skills, assessing the developer's knowledge of security protocols is crucial. With increasing data breaches and cybersecurity threats, your app must be equipped with robust security measures. Developers should demonstrate a clear understanding of encryption techniques, secure backend & API, and adhere to guidelines of OWASP (Open Web Application Security Project).

Finally, after evaluating the developers, it is time to engage in contractual agreements. The contract should clearly outline the project deliverables, timeline, payment terms, intellectual property rights, and confidentiality agreements. Here, it is advisable to have legal counsel to prevent any contractual loopholes and ensure the protection of rights.

In conclusion, hiring the best Android app developer for your project is a multifaceted process, and it should be approached with due diligence. It requires a thorough understanding of your project, a precise evaluation of the developer's skills, and a well-negotiated contract. It is a complex task, yet, with the right approach and considerations, it can lead to the successful realization of your app project. Remember, the developer you hire could be the difference between an app that merely survives and one that thrives.