1. WHO ( 2016 ) Global strategy on human resources for health: workforce 2030.
2. Pew Research Center (2019) Mobile fact sheet.
3. European Commission (2017) Eurostat: individuals - devices used to access the internet.
4. Statistisches Bundesamt (Destatis) (2020).
5. Health app use among US mobile phone owners: a national survey;Krebs;JMIR Mhealth Uhealth,2015