Memory problems are often associated with ageing and are among the most common effects of brain injury. Such problems can severely disrupt daily life and put huge strain on family members and carers. Electronic devices have been used successfully to provide short and timely reminders to memory-impaired individuals. The Memojog project has developed and evaluated a mobile, interactive communication and memory-aid system with elderly and memory-impaired people. The system utilizes current and easily available technology such as the internet and GPRS mobile telephony. This paper will look at the design as well as the successes and limitations of the Memojog system.