Yes, for self-study. No, for distributing commercially.
Using a portable answer key to check your homework is no different from looking up math answers in the back of a textbook. The problem arises only if you: Yes, for self-study
As long as you use the Schritte International Neu 5 B1.1 Arbeitsbuch Lösungen portable as a correction tool, you are accelerating your learning. As long as you use the Schritte International Neu 5 B1
Portability is not without drawbacks. Digital answer keys may lack the contextual explanations that a teacher or a detailed Lösungsheft might provide. Moreover, over-reliance on portable answers can tempt learners to simply copy solutions rather than engage in the cognitive work of solving exercises. Therefore, portability must be paired with pedagogical discipline: using answer keys for verification, not substitution. Additionally, not all learners are technically adept; older or less digitally literate students may find scanning and syncing files cumbersome. not substitution. Additionally
Since the file is portable, revisit old exercises. Three days after doing a chapter (e.g., Lektion B11), re-check 3 random exercises. If you still get them right, you have learned the material.