More and more respondents are answering web surveys using mobile devices. Mobile respondents tend to provide shorter responses to open questions than PC respondents. Using voice recording to answer open-ended questions could increase data quality and help engage groups usually underrepresented in web surveys. Revilla, Couper, Bosch, and Asensio showed that in particular the use of voice recording still presents many challenges, even if it could be a promising tool. This article reports results from a follow-up experiment in which the main goals were to (1) test whether different instructions on how to use the voice recording tool reduce technical and understanding problems, and thereby reduce item nonresponse while preserving data quality and the evaluation of the tool; (2) test whether nonresponse due to context can be reduced by using a filter question, and how this affects data quality and the tool evaluation; and (3) understand which factors affect nonresponse to open-ended questions using voice recording, and if these factors also affect data quality and the evaluation of the tool. The experiment was implemented within a smartphone web survey in Spain focused on Android devices. The results suggest that different instructions did not affect nonresponse to the open questions and had little effect on data quality for those who did answer. Introducing a filter to ensure that people were in a setting that permits voice recording seems useful. Despite efforts to reduce problems, a substantial proportion of respondents are still unwilling or unable to answer open questions using voice recording.