Problems of protecting unstructured information on mobile devices

The relevance of the study was determined by the growing volume of unstructured data in the mobile environment, which required a rethinking of classical approaches to the protection in conditions of limited resources and dynamic use. The purpose of the study was to conduct a comprehensive analysis of methods for protecting unstructured information in the mobile environment and to identify key barriers to the effective implementation. The methodology was based on a theoretical and analytical approach, which included the systematisation of protection methods, a comparative analysis of cryptographic algorithms, an assessment of authentication and access control models, as well as an analysis of cloud security mechanisms. It was established that symmetric encryption Advanced Encryption Standard in Cipher Block Chaining mode provided effective local protection but required careful management of initialisation vectors. It was found that Elliptic Curve Cryptography outperformed Rivest-Shamir-Adleman in terms of energy efficiency and performance, and BLAKE3 outperformed Secure Hash Algorithm 256 in terms of speed, energy consumption, and parallelism support. It was generalised that access control models were insufficiently adapted to the dynamics of the mobile environment, and the most effective were context-oriented and multifactor approaches, in particular with the use of biometric and behavioural authentication. It was found that a combination of client-side encryption, identity management, and cloud backup ensured the highest level of protection with proper implementation. It was established that the effectiveness of HyperText Transfer Protocol Secure, Transport Layer Security 1.3, and Virtual Private Network protocols depended on the type of data and interaction scenario, and the use required a balance between security, performance, and the context of use. Eight key challenges were identified, the relevance of which to mobile security practice was confirmed through comparison with the OWASP Mobile Top 10 categories: data leakage, limited resources, complexity of authentication, dynamic access control, use of public networks, platform fragmentation, application opacity, and legal barriers. It was determined that the effectiveness of protection methods was conditioned by the context of application – the type of data, device architecture, interaction scenario, and available infrastructure – which required an adaptive choice of solutions. The results obtained confirmed that traditional approaches to information security required adaptation to the specifics of mobile platforms. The study has practical value for security solution developers, corporate system administrators, and policymakers in the field of cybersecurity