This contribution researches various translation dictionaries -- mobile apps with Latvian that are available for free on the Google Play Store and sets out the experience of developing specialised translation dictionaries at Ventspils University of Applied Sciences (VUAS). The results encounter three different dictionary models that are compiled for the acquisition of Languages for Special Purposes (LSPs) to support vocabulary (term) learning, translation, reading, listening and writing skills during the foreign language-learning process. Dictionaries with grammatical information and rich, supportive data or encyclopaedic information added are more useful for understanding specific domain concepts and content, as well as for the translation practice. Thus, the dictionary user does not have to look for another application or other source to get this additional information. Each new app takes up some space on the user's smart device; therefore, it is important to maximise the support provided by a single dictionary. The research provides insight into the range of dictionaries with Latvian available on the Google Play Store, gives a brief description, and explains the practical experience of VUAS when working on developing such dictionaries and applying them for language-learning purposes and specialised terminology courses for students. The study also provides an overview of challenges, problems and lexicographic and information technology solutions for mobile applications. The goal of the research is analysing and characterising those free-of-charge dictionaries in the form of mobile apps with Latvian as one of the translation languages. Surveys were used to gather and analyse research data. A survey of dictionary users and a survey of language learners using dictionary apps were carried out after the development of the specialised dictionaries.