Objectives: We evaluated patterns of uptake of the NHS App using data metrics on total app downloads, registrations, appointment bookings, GP health records viewed, prescriptions ordered. Sub-group differences in App registration and the impact of COVID-19 were also explored. Methods: Descriptive statistics and time series analysis explored monthly NHS App use from January 2019-May 2021. Interrupted time series models were used to identify changes in level and trend in use of different functionalities before and after the first COVID-19 lockdown. Negative binomial regression assessed differences in App registration by markers of GP level socio-demographic variables. Results: Between January 2019 and May 2021, there were 8,524,882 NHS App downloads and 4,449,869 registrations. There was a 4-fold increase in App downloads when the COVID Pass feature was introduced. Analyses by socio-demographic data found 25% lower registrations in the most deprived practices (p<0.001), and 44% more registrations in the largest sized practices (p<0.001). Registration rates were 36% higher in practices with the highest proportion of registered white patients (p<0.001), 23% higher in practices with the largest proportion of 15–34-year-olds (p<0.001) and 2% lower in practices with highest proportion of people with long-term care needs (p<0.001). Conclusion: The uptake of the NHS App substantially increased post lockdown, most significantly after the COVID Pass feature was introduced. We identified an unequal pattern of App registration and the use of different functions also varied. Further research is needed to measure the extent of the divide and its impact on patient experience and care outcomes.