Background Pro-smoking applications (app) provide information about brands of tobacco products, where to buy them, and encourage their use. It is unclear in which countries these apps are being downloaded, or whether app stores play a role in promoting or regulating these apps, particularly those that appear to target children.

Method The lifetime popularity of 107 pro-smoking apps was investigated, using a third-party app metrics service that aggregates data from app stores about app download popularity by country. Apps were deemed popular if at any time in their lifespan they achieved a top 25 ranking overall across all apps, or a top 25 ranking in any particular category of apps, such as ‘educational games’.

Results Fifty-eight pro-smoking apps reached ‘popularity’ status in Apple and Android stores in one or more of 49 countries, particularly Italy, Egypt, Germany, Belgium and the USA. The daily downloads in each country ranged from approximately 2000 to 80 000. The Apple store featured five of the pro-smoking apps in various categories, and two apps were featured by the Android market. Two pro-smoking apps in the Apple store were extremely popular in the ‘Educational Games’ and ‘Kids’ Games’ categories.

Conclusions Pro-smoking apps were popular in many countries. Most apps were assigned to entertainment and games categories, with some apps specifically targeting children through placement in categories directed at children. App stores that feature pro-smoking apps may be in violation of tobacco control laws.