Due to the global outbreak of COVID-19, education was suddenly shifted to online platforms. While some institutes were ready for the transfer, others had to use available video conferencing tools for lecturing as a quick resolution. Zoom and Microsoft Teams arose to be the most used tools by institutes of higher education for online lecturing. Despite various reported challenges were attributed to lacking e-learning-related features in these platforms, other challenges were attributed to the usability of these platforms for lecturing activities. This study aims at evaluating the usability of Zoom and Teams for online lecturing activities based on a new set of heuristics focusing on cognitive styles. A thorough and systematic usability study is conducted based on the proposed heuristics. As a result of this evaluation, a set of critical, unmet user needs are identified and scored against the proposed heuristics. In addition, a set of guidelines are proposed to support informed selection of online lecturing platforms.