I like that it's free, easy to use with an intuitive interface even if you're new or are not very familiar with online chat apps (it works as well in mobile). It integrates perfectly into Slack! The only downside of this app compared to other options available out there would be their lack of integrations when using Trello boards/tables but again - they do offer many great 3rd party plugins which can help solve these issues. We have used both Zoom & Skype before so we had some expectations going in about how each one might compare against our needs at work where communication between colleagues from different offices was important. What makes us happy here most now? Our ability to communicate effectively across time zones without relying solely upon phone calls / video conferencing.