Torus has a range of providers to allow your users to purchase cryptocurrencies directly with Credit Card/Wire Transfer. Developers can either access this through presenting the "Topup" page below, or trigger the FIAT-to-Crypto providers directly from the API.
Its worth noting that as the FIAT-to-Crypto landscape is a complex and regulated industry, each provider comes with their pros and cons. For example; although Wyre (at the time of writing) has the lowest fees but it's processers require US based cards, access to Simplex is global but it must be accessed through the Torus UI. Before choosing and integrating, it is worth exploring which provider suits your users best.
Providing multiple FIAT-to-Crypto providers give Dapps access to the many different currencies their users can interact with, including but not limited to; BTC, ETH, DAI, BNB. Giving your users the choice allows them to select based what suits them best.