A mobile website is very similar to any other website, and it requires the internet to work. If you are not connected to the internet, you will not be able to access the website. The same cannot be said about a mobile application. There are many cases where mobile applications work without an internet connection, but there are many internet-based apps which are useless without an internet connection.
With both you have immediate access, you have great compatibility, and even upgradability. They are also easily found, and you can even share information about them instantly. At US Troop, we make sure that we do our job when it comes to making mobile apps and creating new mobile websites because we know how important they can be.