1. Apple | use multi-touch gestures on your Mac - Apple support.
https://support.apple.com/en-us/HT204895
. Accessed June 2019
2. Apple developer | gestures - user interaction - IOS - human interface guidelines.
https://developer.apple.com/design/human-interface-guidelines/ios/user-interaction/gestures/
. Accessed June 2019
3. Apple developer | UI design dos and donts.
https://developer.apple.com/design/tips/
. Accessed June 2019
4. kolenda, N.: Psychology and business.
https://www.nickkolenda.com/user-experience/#
. Accessed June 2019
5. World Usability Congress: Touch screen usability best practices when designing automation user interfaces (UI).
https://worldusabilitycongress.com/touch-screen-usability-best-practices-when-designing-automation-user-interfaces-ui/
. Accessed June 2019