The most helpful thing about notifyvisitor is that it helps me to get more leads and sales. I have used notifications in many applications but this one has been really useful. Also I like the option of setting up different notification types as per my liking. The best part is that we can use it even if our website is down or slow. It's a great tool which will help you reach your target audience. I would say nothing much since it's working fine so far. But there are some minor issues related to performance of the website but they are easily resolved. We are solving our problems by sending push notifications to all our clients.