I have a 5 year old samsung and, same as linni, the app stopped working last year. Before that it was not working perfectly, I could not use all features.
Watching it on a browser is possible but inconvenient because the browser itself is not very good. And you can only get the live picture, no rewatching or anything else.
Right now I am mirroring the picture to TV from my smartphone app. Works perfectly, obvious downside is that I cannot use the phone at the same time. So I have the picture running on my PC as well as backup.