Internet usage via mobile phone or smartphone in Germany 2013-2016

Base: German-speaking population, 14 years and older, in private households in the place of their principle residence in Germany.

Random samples:
2013: 25,677 respondents, projected to a population of 70.33 million
2014: 25,363 respondents, projected to a population of 70.52 million
2015: 7,009 respondents, projected to a population of 69.24 million
2016: 7.026 respondents, projected to a population of 69,56 million Personen

The question in the survey was phrased in the following manner: "From which other (additional) sources do you use the internet? Please tell me according to the list here!" Possible answers: directly via mobile phone, smartphone.
(Original German question: "Von wo aus nutzen Sie das Internet sonst (noch)? Bitte sagen Sie mir nach dieser Liste hier!" Antwortmöglichkeit: Direkt über das Handy, das Smartphone.)