Mobile technologies can support learning across different contexts as their portability enables them to be used by the learner in whichever context she or he is in. They can be particularly beneficial in informal and semiformal contexts where learners have more control over their learning goals and where motivation is often high. Inquiries in informal contexts are likely to be personally relevant in terms of topics of interest and capitalise on learners' location as learners decide what, where, when and whether to learn. There is considerable interest in how such benefits can be harnessed for more formal learning and one challenge is how to make inquiries personally relevant in such contexts. However, there is little literature that considers the structure needed to support informal and semiformal inquiry learning. This paper contributes to that literature by examining dimensions for researchers and designers to consider investigating or developing support for inquiries in informal or semiformal settings. The paper examines two case studies of inquiry learning in contrasting settings in order to understand more about learner control and how technology can support learners' inquiries. Case study one considers the use of web based software to support science inquiry learning by 14-15 year olds in a semiformal context, whilst the second case study reports on informal adult learners using their own mobile technologies to learn about landscape. These case studies are compared and contrasted in terms of the dimensions of learner control, location of learning, and the different support mechanisms for inquiry learning and a framework is proposed for considering these dimensions. (Contains 2 tables and 4 figures.)