This is open source software, use at your own risk. There is always a tradeoff between ease of use and security (that's why you don't live in a bunker). By not requiring your potential sources to install an app, there is a risk that a hacker could tamper with the files served to them to include a key logger. Depending on your threat model, this may or may not matter. It’s all about finding the appropriate tool for the job. Read more about the security of Tipbox.