We developed the taxonomy which is composed of three different classes. Each one results into a method and a related hidden channel with a well-defined scope of Smartphone Objects Methods the key idea is to use digital objects produced and handled by modern. The available solutions are plain ports, and the related literature introduces little novelty, with the only notable exception of steganographic approaches based on Quick Response (QR) codes. Generally, steganography mitigation techniques aim at: i) detecting, ii) eliminating, and iii) limiting the steganographic bandwidth (or capacity) of a covert channel. Especially, for i) there is a well-defined research area called steganalysis, while for ii) and iii) the lack of universal solutions stems countermeasures tightly coupled with the specific information hiding technique. The diffusion of the cloud-based paradigm enables a variety of services moving data from the device to the Internet (and vice versa). In this vein, a plethora of new patterns should be investigated as possible steganography carriers.