I find the title misleading.
typst.app is not a Latex editor. typst has its own syntax and own compiler to generate PDFs.
the cli is FOSS (theres a great plugin for vscode), typst.app is their SaaS Overleaf-equivalent to collaborate on papers. you write .typ, not .tex files. arguably a more modern and easier to read syntax. :)
can recommend if you want something simple. its not there yet in terms of featureset, but its getting there. also its quick and the UX is leagues ahead of latex