Being an informal caregiver is not easy, and might cause physical and psychosocial burden, especially in the long run. However, the formal health care system has little support for informal caregivers who experience abandonment and lack information. Mobile health can potentially be an efficient and cost-effective way of supporting informal caregivers. However, research has shown that mHealth systems often have problems with usability, and people do not use the systems for more than a short period. Therefore, this paper explores the design of an mHealth app using Persuasive Design, an established design framework. This paper presents the design of the first version of the e-coaching application using the persuasive design framework and unmet needs of informal caregivers from the literature. This prototype version will be updated based on interview data from informal caregivers in Sweden.