Continuous use of cognitive training APP plays an important role in improving cognitive functions of older adults with mild cognitive impairment (MCI). The work aims to explore the key factors affecting users' continuance intention and provide feasible suggestions for APP design. A model of factors influencing users' continuous intention was constructed based on the UTAUT and the HBM. Hypotheses were proposed. The model was empirically tested. Significant influencing factors along with their coefficient magnitudes were identified. An in-depth analysis of the relationships among these significant factors was conducted, and corresponding design strategies were generated to guide APP development. PE, EE, SI, FC, PBN, SE, and CTA had a significant positive impact on users' continuance intention. PBR had a significant negative impact, while PSS and PPSV had no effect. Among these factors, EE had the largest impact coefficient. The commonalities between the factors were synthesized through the Delphi method to form a corresponding design strategy, and the results of the MAUQ questionnaire indicate that the cognitive training APP adopting this design strategy shows a higher intention of users to continue using it.