This study investigated student perceptions and opinions on an English Oral Presentation Application (EOPA), a mobile learning application designed to assist English learners develop oral presentations and online collaboration skills. This study was part of a Design Based Research (DBR) project which incorporated an adapted Technology Acceptance Model (TAM) questionnaire to gain insights on students' perceptions towards EOPA. In addition, focus-group interviews were used to discover the external and internal factors involved in this type of mobile learning. Participants were 30 Taiwanese undergraduate students who took part in a six-week training course. The questionnaire results indicated that 37% of students found EOPA to be useful for learning, but 33% also found it inconvenient to use. Furthermore, attitudes towards learning suggested they had some difficulties using the app. To gain a deeper understanding of why students use EOPA and to discover other app-related learning problems, the interviews were explored using a Complex Dynamic Systems approach to find the attractor and repeller dynamic states in the learning system. These included the language and presentation skills, the multimedia learning material, app design, online collaboration, anxiety, and limited self-regulation skills. The findings will be used to refine EOPA and the oral presentation learning framework. The study demonstrates how the discovery of different dynamic states can be used to improve mobile learning design.