Tor is a free and open-source software made for the realization of onion routing, the technology of anonymous information exchange. In addition, Tor has two official versions of its browser which are the Tor Browser and TorBro — aimed to be a more anonymous alternative of the Tor Browser. The Tor Browser is also available on smartphones as Onion Tor Browser. The main purpose of using the Tor Browser is to remain anonymous and avoid censorship by disguising an IP-address. Like Tor, Bitcoin has the reputation of being anonymous and, by that, draws the attention of various security agencies. Nevertheless, some experts warn about the unsecure nature of transactions in cryptocurrency made on Tor, as there is a higher risk of money being stolen.