## 4 Discussion  
### RQ1: Linguistic Competence  
The current study results indicate that those students who accomplished the learning task using the digital version (ExpGr) made more writing mistakes than those who accomplished it using the paper version (ContGr). This leads to the assumption that making more mistakes could be related to the added difficulty of using a virtual keyboard, the lack of experience with using the digital version, and the use of a more informal language (usually linked to communications via text chat). Another factor that might have caused the higher number of mistakes in the ExpGr could be the pressure students felt when there were several threads of open conversation in which activities were negotiated.  
Terminkalender in its digital format encourages faster and, therefore, less reflective communication during which language learners make more mistakes, paying less attention to formal language aspects, and use fewer complex structures (e.g., nominal phrases, adjectival phrases, prepositional phrases, etc.). This finding suggests that the digital version is less appropriate for developing students' linguistic competence than the paper version.  
Likewise, the results of the study seem to reinforce the claims of previous studies [52; 53; 54; 55] that observed differences at the cognitive level between students who accomplished a learning task by handwriting and those who used a virtual keyboard. Handwriting seems to help those who write the words themselves to focus more attentively on the words they write, while writing by means of a virtual keyboard often divides the attention of those who write between controlling and correctly choosing the letters and words from  
Figure 11: Descriptive plot showing significant differences between both groups regarding the number of messages sent (M) and turns (T).  
the keyboard to compose a sentence. The latter can finally affect students' cognitive process and result in worse retention of words [52].  
In line with the analyzed data, the authors of the current study can confirm that the ContrGr employed a greater variety of words and expressions from those previously used in class than the ExpGr. This means that the ContrGr employed a much richer and more diversified language compared to the ExpGr. The results, therefore, suggest that the paper version could be more adequate than the digital version for applying and practicing the lexical, grammatical and morphosyntactic knowledge previously acquired in class.  
Regarding the complexity of students' writing, it stands out that students employed shorter sentences when they accomplished the task using the digital version. The fact that the digital version invites students to use simpler syntactic structures (based on nominal, verbal, or adjectival phrases, etc.) seems to indicate that the digital version encourages its users to prioritize fast and immediate communication while, at the same time, paying less attention to formal language aspects. This can be an argument against (cons) the digital version, since excessive simplification of the syntactic structures used could be an obstacle to the development of students' linguistic competence.