They raised 25k via donations & 370k via VC. Longterm they plan to offer additional app icons and user profile badges to project sponsors (similar to Signal), and earn money by operating parts of the network (e.g. high performance & commercial servers) without owning the network. See the blog post for more information: https://simplex.chat/blog/20230422-simplex-chat-vision-funding-v5-videos-files-passcode.html#why-is-it-a-commercial-company