At some point in the future we would like to be able to support additional browsers, including Safari, however we do not have an ETA.
There are some browsers which have been built on the Chromium browser engine, which is an offshoot of Chrome. As such, many of these browsers are able to install Chrome extensions. PLEASE NOTE that while our extension may be able to be installed on to these browsers, we are not able to support any malfunctions which may ensue.
Additionally, we are currently working diligently on our first ever mobile app. We are expecting to launch soon, so stay tuned for a public announcement!