Objective: This review aimed to determine the effectiveness of personal smart technologies on outcomes in adults with acquired brain injury. Data sources: A systematic literature search was conducted on 30 May 2019. Twelve electronic databases, grey literature databases, PROSPERO, reference list and author citations were searched. Methods: Randomised controlled trials were included if personal smart technology was used to improve independence, goal attainment/function, fatigue or quality of life in adults with acquired brain injury. Data were extracted using a bespoke form and the TIDieR checklist. Studies were graded using the PEDro scale to assess quality of reporting. Meta-analysis was conducted across four studies. Results: Six studies met the inclusion criteria, generating a total of 244 participants. All studies were of high quality (PEDro ⩾ 6). Interventions included personal digital assistant, smartphone app, mobile phone messaging, Neuropage and an iPad. Reporting of intervention tailoring for individual needs was inconsistent. All studies measured goal attainment/function but none measured independence or fatigue. One study ( n = 42) reported a significant increase in memory-specific goal attainment ( p = 0.0001) and retrospective memory function ( p = 0.042) in favour of the intervention. Another study ( n = 8) reported a significant increase in social participation in favour of the intervention ( p = 0.01). However, our meta-analyses found no significant effect of personal smart technology on goal attainment, cognitive or psychological function. Conclusion: At present, there is insufficient evidence to support the clinical benefit of personal smart technologies to improve outcomes in acquired brain injury. Researchers need to conduct more randomised studies to evaluate these interventions and measure their potential effects/harms.